diff --git a/src/address.ts b/src/address.ts
index 7e6b0fdcc4e..c510b46c040 100644
--- a/src/address.ts
+++ b/src/address.ts
@@ -235,6 +235,7 @@ export class Address {
    */
   secondaryAddress(): string {
     return this.Helpers.replaceSymbolWithNumber(
+      // TODO ST-DDT 2022-01-30: this.faker.definitions.address.secondary_address
       this.faker.random.arrayElement(['Apt. ###', 'Suite ###'])
     );
   }
diff --git a/src/definitions.ts b/src/definitions.ts
deleted file mode 100644
index db142429ba3..00000000000
--- a/src/definitions.ts
+++ /dev/null
@@ -1,131 +0,0 @@
-export interface Definitions {
-  address: {
-    city_name;
-    city_prefix;
-    city_suffix;
-    country_code_alpha_3;
-    country_code;
-    country;
-    county;
-    direction_abbr;
-    direction;
-    postcode_by_state;
-    postcode: string | string[];
-    state_abbr;
-    state;
-    street_prefix;
-    street_suffix;
-    time_zone;
-  };
-  animal: {
-    bear;
-    bird;
-    cat;
-    cetacean;
-    cow;
-    crocodilia;
-    dog;
-    fish;
-    horse;
-    insect;
-    lion;
-    rabbit;
-    snake;
-    type;
-  };
-  commerce: {
-    color;
-    department;
-    product_description;
-    product_name;
-  };
-  company: {
-    adjective;
-    bs_adjective;
-    bs_noun;
-    bs_verb;
-    descriptor;
-    noun;
-    suffix;
-  };
-  database: {
-    collation;
-    column;
-    engine;
-    type;
-  };
-  date: {
-    month;
-    weekday;
-  };
-  finance: {
-    account_type;
-    credit_card;
-    currency: Record<string, { code: string; symbol: string }>;
-    transaction_type;
-  };
-  hacker: {
-    abbreviation;
-    adjective;
-    ingverb;
-    noun;
-    phrase;
-    verb;
-  };
-  internet: {
-    domain_suffix;
-    example_email;
-    free_email;
-  };
-  lorem: {
-    words;
-  };
-  music: {
-    genre;
-  };
-  name: {
-    binary_gender;
-    female_first_name;
-    female_last_name;
-    female_middle_name;
-    female_prefix;
-    first_name;
-    gender;
-    last_name;
-    male_first_name;
-    male_last_name;
-    male_middle_name;
-    male_prefix;
-    middle_name;
-    prefix;
-    suffix;
-    title: {
-      descriptor;
-      level;
-      job;
-    };
-  };
-  phone_number: {
-    formats;
-  };
-  system: {
-    directoryPaths;
-    mimeTypes;
-  };
-  vehicle: {
-    bicycle_type;
-    fuel;
-    manufacturer;
-    model;
-    type;
-  };
-  word: {
-    adjective: string[];
-    adverb: string[];
-    conjunction: string[];
-    interjection: string[];
-    noun: string[];
-    preposition: string[];
-    verb: string[];
-  };
-}
diff --git a/src/definitions/address.ts b/src/definitions/address.ts
new file mode 100644
index 00000000000..a5bf2d1c861
--- /dev/null
+++ b/src/definitions/address.ts
@@ -0,0 +1,115 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to addresses.
+ */
+export interface AddressDefinitions {
+  /**
+   * Postcodes patterns by state
+   */
+  // TODO ST-DDT 2022-01-31: address.zipCodeByState() expects only { [state: string]: { min: number; max: number } }
+  postcode_by_state:
+    | string[]
+    | { [state: string]: { min: number; max: number } };
+  /**
+   * Postcodes patterns (Fake-Pattern | Fake-Pattern[]).
+   */
+  postcode: string | string[];
+
+  /**
+   * Names of actual cities
+   */
+  city_name?: string[];
+  /**
+   * Common city prefixes
+   */
+  city_prefix: string[];
+  /**
+   * Common city suffixes
+   */
+  city_suffix: string[];
+
+  /**
+   * The names of all countries
+   */
+  country: string[];
+  /**
+   * The names of this country's states
+   */
+  state: string[];
+  /**
+   * The abbreviated names of this country's states
+   */
+  state_abbr: string[];
+  /**
+   * The names of counties inside the country or state
+   */
+  county: string[];
+
+  /**
+   * The names of the compass directions.
+   * First the 4 cardinal directions, then the 4 ordinal directions
+   */
+  direction: string[];
+  /**
+   * The abbreviated names of the compass directions.
+   * First the 4 cardinal directions, then the 4 ordinal directions
+   */
+  direction_abbr: string[];
+
+  /**
+   * Common street prefixes
+   */
+  street_prefix: string[];
+  /**
+   * Common street suffixes
+   */
+  street_suffix: string[];
+
+  /**
+   * The address "inside" an address/e.g. an apartment or office.
+   */
+  secondary_address: string[];
+
+  /**
+   * The ISO-3166-1 ALPHA-2 country codes
+   */
+  country_code: string[];
+  /**
+   * The ISO-3166-1 ALPHA-3 country codes
+   */
+  country_code_alpha_3: string[];
+
+  // A list of timezones names.
+  time_zone: string[];
+}
+
+/**
+ * Internal: A list of all keys for the AddressDefinitions.
+ */
+export const ADDRESS = allOf<keyof AddressDefinitions>()(
+  'postcode_by_state',
+  'postcode',
+
+  'city_name',
+  'city_prefix',
+  'city_suffix',
+
+  'country',
+  'state',
+  'state_abbr',
+  'county',
+
+  'direction_abbr',
+  'direction',
+
+  'street_prefix',
+  'street_suffix',
+
+  'secondary_address',
+
+  'country_code',
+  'country_code_alpha_3',
+
+  'time_zone'
+);
diff --git a/src/definitions/animal.ts b/src/definitions/animal.ts
new file mode 100644
index 00000000000..68fe0db24ae
--- /dev/null
+++ b/src/definitions/animal.ts
@@ -0,0 +1,41 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to animals.
+ */
+export interface AnimalDefinitions {
+  bear: string[];
+  bird: string[];
+  cat: string[];
+  cetacean: string[];
+  cow: string[];
+  crocodilia: string[];
+  dog: string[];
+  fish: string[];
+  horse: string[];
+  insect: string[];
+  lion: string[];
+  rabbit: string[];
+  snake: string[];
+  type: string[];
+}
+
+/**
+ * Internal: A list of all keys for the AnimalDefinitions.
+ */
+export const ANIMAL = allOf<keyof AnimalDefinitions>()(
+  'dog',
+  'cat',
+  'snake',
+  'bear',
+  'lion',
+  'cetacean',
+  'insect',
+  'crocodilia',
+  'cow',
+  'bird',
+  'fish',
+  'rabbit',
+  'horse',
+  'type'
+);
diff --git a/src/definitions/commerce.ts b/src/definitions/commerce.ts
new file mode 100644
index 00000000000..dbe22f69949
--- /dev/null
+++ b/src/definitions/commerce.ts
@@ -0,0 +1,51 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to commerce.
+ */
+export interface CommerceDefinitions {
+  /**
+   * Human readable color names
+   */
+  color: string[];
+  /**
+   * Department names inside a shop.
+   */
+  department: string[];
+  /**
+   * Product name generation definitions.
+   */
+  product_name: CommerceProductNameDefinitions;
+  /**
+   * Descriptions for products.
+   */
+  product_description: string[];
+}
+
+/**
+ * The possible definitions related to product name generation.
+ */
+export interface CommerceProductNameDefinitions {
+  /**
+   * Adjectives describing a product (e.g. tasty).
+   */
+  adjective: string[];
+  /**
+   * Materials describing a product (e.g. wood).
+   */
+  material: string[];
+  /**
+   * Types of products (e.g. chair).
+   */
+  product: string[];
+}
+
+/**
+ * Internal: A list of all keys for the CommerceDefinitions.
+ */
+export const COMMERCE = allOf<keyof CommerceDefinitions>()(
+  'color',
+  'department',
+  'product_name',
+  'product_description'
+);
diff --git a/src/definitions/company.ts b/src/definitions/company.ts
new file mode 100644
index 00000000000..35947bde9f7
--- /dev/null
+++ b/src/definitions/company.ts
@@ -0,0 +1,50 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to companies.
+ */
+export interface CompanyDefinitions {
+  /**
+   * Business/products related adjectives.
+   */
+  bs_adjective: string[];
+  /**
+   * Business/products related nouns.
+   */
+  bs_noun: string[];
+  /**
+   * Business/products related verbs.
+   */
+  bs_verb: string[];
+  /**
+   * Catch phrase adjectives.
+   */
+  adjective: string[];
+  /**
+   * Catch phrase adjectives.
+   */
+  descriptor: string[];
+  /**
+   * Catch phrase adjectives.
+   */
+  noun: string[];
+  /**
+   * Company suffixes
+   */
+  suffix: string[];
+}
+
+/**
+ * Internal: A list of all keys for the CompanyDefinitions.
+ */
+export const COMPANY = allOf<keyof CompanyDefinitions>()(
+  'bs_adjective',
+  'bs_noun',
+  'bs_verb',
+
+  'adjective',
+  'descriptor',
+  'noun',
+
+  'suffix'
+);
diff --git a/src/definitions/database.ts b/src/definitions/database.ts
new file mode 100644
index 00000000000..935f35fcd98
--- /dev/null
+++ b/src/definitions/database.ts
@@ -0,0 +1,33 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to databases.
+ */
+export interface DatabaseDefinitions {
+  /**
+   * Database Engine
+   */
+  engine: string[];
+  /**
+   * Database Collation
+   */
+  collation: string[];
+  /**
+   * Column names
+   */
+  column: string[];
+  /**
+   * Column types
+   */
+  type: string[];
+}
+
+/**
+ * Internal: A list of all keys for the DatabaseDefinitions.
+ */
+export const DATABASE = allOf<keyof DatabaseDefinitions>()(
+  'collation',
+  'column',
+  'engine',
+  'type'
+);
diff --git a/src/definitions/date.ts b/src/definitions/date.ts
new file mode 100644
index 00000000000..2738bdb5e84
--- /dev/null
+++ b/src/definitions/date.ts
@@ -0,0 +1,44 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to dates.
+ */
+export interface DateDefinitions {
+  /**
+   * The translations for months (January - December).
+   */
+  month: DateEntryDefinition;
+  /**
+   * The translations for weekdays (Sunday - Saturday).
+   */
+  weekday: DateEntryDefinition;
+}
+
+/**
+ * The possible definitions related to date entries.
+ */
+export interface DateEntryDefinition {
+  /**
+   * The long name of the entry.
+   */
+  wide: string[];
+  /**
+   * The short name/abbreviation of the entry.
+   */
+  abbr: string[];
+  /**
+   * The wide name of the entry when used in context. If absent wide will be used instead.
+   * It is used to specify a word in context, which may differ from a stand-alone word.
+   */
+  wide_context?: string[];
+  /**
+   * The short name/abbreviation name of the entry when used in context. If absent abbr will be used instead.
+   * It is used to specify a word in context, which may differ from a stand-alone word.
+   */
+  abbr_context?: string[];
+}
+
+/**
+ * Internal: A list of all keys for the DateDefinitions.
+ */
+export const DATE = allOf<keyof DateDefinitions>()('month', 'weekday');
diff --git a/src/definitions/definitions.ts b/src/definitions/definitions.ts
new file mode 100644
index 00000000000..d59f84fc859
--- /dev/null
+++ b/src/definitions/definitions.ts
@@ -0,0 +1,111 @@
+import type { AddressDefinitions } from './address';
+import { ADDRESS } from './address';
+import type { AnimalDefinitions } from './animal';
+import { ANIMAL } from './animal';
+import type { CommerceDefinitions } from './commerce';
+import { COMMERCE } from './commerce';
+import type { CompanyDefinitions } from './company';
+import { COMPANY } from './company';
+import type { DatabaseDefinitions } from './database';
+import { DATABASE } from './database';
+import type { DateDefinitions } from './date';
+import { DATE } from './date';
+import type { FinanceDefinitions } from './finance';
+import { FINANCE } from './finance';
+import type { HackerDefinitions } from './hacker';
+import { HACKER } from './hacker';
+import type { InternetDefinitions } from './internet';
+import { INTERNET } from './internet';
+import type { LoremDefinitions } from './lorem';
+import { LOREM } from './lorem';
+import type { MusicDefinitions } from './music';
+import { MUSIC } from './music';
+import type { NameDefinitions } from './name';
+import { NAME } from './name';
+import type { PhoneNumberDefinitions } from './phone_number';
+import { PHONE_NUMBER } from './phone_number';
+import type { SystemDefinitions } from './system';
+import { SYSTEM } from './system';
+import type { VehicleDefinitions } from './vehicle';
+import { VEHICLE } from './vehicle';
+import type { WordDefinitions } from './word';
+import { WORD } from './word';
+
+/**
+ * The definitions as used by the Faker modules.
+ */
+interface Definitions {
+  address: AddressDefinitions;
+  animal: AnimalDefinitions;
+  commerce: CommerceDefinitions;
+  company: CompanyDefinitions;
+  database: DatabaseDefinitions;
+  date: DateDefinitions;
+  finance: FinanceDefinitions;
+  hacker: HackerDefinitions;
+  internet: InternetDefinitions;
+  lorem: LoremDefinitions;
+  music: MusicDefinitions;
+  name: NameDefinitions;
+  phone_number: PhoneNumberDefinitions;
+  system: SystemDefinitions;
+  vehicle: VehicleDefinitions;
+  word: WordDefinitions;
+}
+
+/**
+ * The definitions as used by the translations/locales.
+ * This is basically the same as Definitions with the exception,
+ * that most properties are optional and extra properties are allowed.
+ */
+export type LocaleDefinition = {
+  /**
+   * The name of the language.
+   */
+  title: string;
+  separator?: string;
+} & {
+  // Known modules
+  [module in keyof Definitions]?: Partial<Definitions[module]>;
+} & {
+  // Unsupported & custom modules
+  [group: string]: Record<string, any> | string;
+};
+
+/**
+ * Internal: Compatibility type to ensure all modules have access to fallback locales.
+ * This should be replaced with a Proxy based property access
+ * that don't require prior getter generation in the future.
+ */
+export type DefinitionTypes = {
+  readonly title: string;
+  readonly separator: string;
+} & {
+  readonly [module in keyof Definitions]: Array<keyof Definitions[module]>;
+};
+
+/**
+ * Internal: List off all modules and their properties,
+ * that needs to have a fallback generated in Faker.loadDefinitions().
+ */
+export const DEFINITIONS: DefinitionTypes = {
+  title: '',
+  separator: '',
+
+  address: ADDRESS,
+  animal: ANIMAL,
+  company: COMPANY,
+  commerce: COMMERCE,
+  database: DATABASE,
+  date: DATE,
+  finance: FINANCE,
+  hacker: HACKER,
+  internet: INTERNET,
+  lorem: LOREM,
+  music: MUSIC,
+  name: NAME,
+  phone_number: PHONE_NUMBER,
+  system: SYSTEM,
+  vehicle: VEHICLE,
+  word: WORD,
+};
diff --git a/src/definitions/finance.ts b/src/definitions/finance.ts
new file mode 100644
index 00000000000..afe3639b5b4
--- /dev/null
+++ b/src/definitions/finance.ts
@@ -0,0 +1,50 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to finances.
+ */
+export interface FinanceDefinitions {
+  /**
+   * The types of accounts/purposes of an account (e.g. `Savings` account).
+   */
+  account_type: string[];
+  /**
+   * The pattern by provider used to generate credit card codes.
+   * `L` will be replaced by the check bit.
+   *
+   * @see Helpers.replaceCreditCardSymbols()
+   */
+  credit_card: { [provider: string]: string[] };
+  /**
+   * Currencies by their full name and their symbols (e.g. `US Dollar` -> `USD` / `$`).
+   */
+  currency: { [currencyName: string]: FinanceCurrencyEntryDefinitions };
+  /**
+   * Types of transactions (e.g. `deposit`).
+   */
+  transaction_type: string[];
+}
+
+/**
+ * The possible definitions related to currency entries.
+ */
+export interface FinanceCurrencyEntryDefinitions {
+  /**
+   * The code/short text/abbreviation for the currency (e.g. `USD`).
+   */
+  code: string;
+  /**
+   * The symbol for the currency (e.g. `$`).
+   */
+  symbol: string;
+}
+
+/**
+ * Internal: A list of all keys for the FinanceDefinitions.
+ */
+export const FINANCE = allOf<keyof FinanceDefinitions>()(
+  'account_type',
+  'credit_card',
+  'currency',
+  'transaction_type'
+);
diff --git a/src/definitions/hacker.ts b/src/definitions/hacker.ts
new file mode 100644
index 00000000000..00aa3a40875
--- /dev/null
+++ b/src/definitions/hacker.ts
@@ -0,0 +1,47 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to computers.
+ */
+export interface HackerDefinitions {
+  /**
+   * Generic computer related abbreviations (e.g. `RAM`, `EXE`).
+   */
+  abbreviation: string[];
+  /**
+   * Some computer related adjectives or descriptors (e.g. `digital`, `bluetooth`)
+   */
+  adjective: string[];
+  /**
+   * Some computer related verbs for continuous actions (en: `ing` suffix; e.g. `hacking`).
+   */
+  ingverb: string[];
+  /**
+   * Some computer related nouns (e.g. `protocol`, `sensor`)
+   */
+  noun: string[];
+  /**
+   * Some phrases that will be injected with random hacker words.
+   * May use any of the HackerDefinition keys wrapped in double braces.
+   * (e.g. `I'm {{ingverb}} {{adjective}} {{noun}}` )
+   *
+   * @see Helpers.mustache()
+   */
+  phrase: string[];
+  /**
+   * Some computer related verbs (e.g. `hack`).
+   */
+  verb: string[];
+}
+
+/**
+ * Internal: A list of all keys for the HackerDefinitions.
+ */
+export const HACKER = allOf<keyof HackerDefinitions>()(
+  'abbreviation',
+  'adjective',
+  'ingverb',
+  'noun',
+  'phrase',
+  'verb'
+);
diff --git a/src/definitions/index.ts b/src/definitions/index.ts
new file mode 100644
index 00000000000..e4659e0afe6
--- /dev/null
+++ b/src/definitions/index.ts
@@ -0,0 +1,27 @@
+export type { AddressDefinitions } from './address';
+export type { AnimalDefinitions } from './animal';
+export type {
+  CommerceDefinitions,
+  CommerceProductNameDefinitions,
+} from './commerce';
+export type { CompanyDefinitions } from './company';
+export type { DatabaseDefinitions } from './database';
+export type { DateDefinitions, DateEntryDefinition } from './date';
+export type { DefinitionTypes, LocaleDefinition } from './definitions';
+export { DEFINITIONS } from './definitions';
+export type {
+  FinanceCurrencyEntryDefinitions,
+  FinanceDefinitions,
+} from './finance';
+export type { HackerDefinitions } from './hacker';
+export type { InternetDefinitions } from './internet';
+export type { LoremDefinitions } from './lorem';
+export type { MusicDefinitions } from './music';
+export type { NameDefinitions, NameTitleDefinitions } from './name';
+export type { PhoneNumberDefinitions } from './phone_number';
+export type {
+  SystemDefinitions,
+  SystemMimeTypeEntryDefinitions,
+} from './system';
+export type { VehicleDefinitions } from './vehicle';
+export type { WordDefinitions } from './word';
diff --git a/src/definitions/internet.ts b/src/definitions/internet.ts
new file mode 100644
index 00000000000..55448841d8c
--- /dev/null
+++ b/src/definitions/internet.ts
@@ -0,0 +1,28 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to internet stuff.
+ */
+export interface InternetDefinitions {
+  /**
+   * Common top level and similar domains (e.g `de`, `co.uk`).
+   */
+  domain_suffix: string[];
+  /**
+   * Some email domains containing `example` (e.g. `example.com`).
+   */
+  example_email: string[];
+  /**
+   * Some free-mail domains used in that country (e.g. `gmail.de`).
+   */
+  free_email: string[];
+}
+
+/**
+ * Internal: A list of all keys for the InternetDefinitions.
+ */
+export const INTERNET = allOf<keyof InternetDefinitions>()(
+  'domain_suffix',
+  'example_email',
+  'free_email'
+);
diff --git a/src/definitions/lorem.ts b/src/definitions/lorem.ts
new file mode 100644
index 00000000000..eb548e46fd4
--- /dev/null
+++ b/src/definitions/lorem.ts
@@ -0,0 +1,16 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to lorem texts.
+ */
+export interface LoremDefinitions {
+  /**
+   * Lorem words used to generate dummy texts.
+   */
+  words: string[];
+}
+
+/**
+ * Internal: A list of all keys for the LoremDefinitions.
+ */
+export const LOREM = allOf<keyof LoremDefinitions>()('words');
diff --git a/src/definitions/music.ts b/src/definitions/music.ts
new file mode 100644
index 00000000000..1f2ffdd80bd
--- /dev/null
+++ b/src/definitions/music.ts
@@ -0,0 +1,16 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to music.
+ */
+export interface MusicDefinitions {
+  /**
+   * The names of some music genres.
+   */
+  genre: string[];
+}
+
+/**
+ * Internal: A list of all keys for the MusicDefinitions.
+ */
+export const MUSIC = allOf<keyof MusicDefinitions>()('genre');
diff --git a/src/definitions/name.ts b/src/definitions/name.ts
new file mode 100644
index 00000000000..57926649b09
--- /dev/null
+++ b/src/definitions/name.ts
@@ -0,0 +1,73 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to people's names.
+ */
+export interface NameDefinitions {
+  gender: string[];
+  binary_gender: string[];
+
+  prefix?: string[];
+  female_prefix?: string[];
+  male_prefix?: string[];
+
+  first_name?: string[];
+  female_first_name?: string[];
+  male_first_name?: string[];
+
+  middle_name?: string[];
+  female_middle_name?: string[];
+  male_middle_name?: string[];
+
+  last_name?: string[];
+  female_last_name?: string[];
+  male_last_name?: string[];
+
+  suffix: string[];
+
+  /**
+   * A list of patterns used to generate names (Fake-Pattern[]).
+   */
+  name: string[];
+
+  title: NameTitleDefinitions;
+}
+
+/**
+ * The possible definitions related to people's titles.
+ */
+export interface NameTitleDefinitions {
+  descriptor?: string[];
+  job: string[];
+  level?: string[];
+}
+
+/**
+ * Internal: A list of all keys for the NameDefinitions.
+ */
+export const NAME = allOf<keyof NameDefinitions>()(
+  'gender',
+  'binary_gender',
+
+  'prefix',
+  'female_prefix',
+  'male_prefix',
+
+  'first_name',
+  'female_first_name',
+  'male_first_name',
+
+  'middle_name',
+  'female_middle_name',
+  'male_middle_name',
+
+  'last_name',
+  'female_last_name',
+  'male_last_name',
+
+  'suffix',
+
+  'name',
+
+  'title'
+);
diff --git a/src/definitions/phone_number.ts b/src/definitions/phone_number.ts
new file mode 100644
index 00000000000..ed7353b552d
--- /dev/null
+++ b/src/definitions/phone_number.ts
@@ -0,0 +1,21 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to phone numbers.
+ */
+export interface PhoneNumberDefinitions {
+  /**
+   * Some patterns used to generate phone numbers.
+   * `#` will be replaced by a random digit (0-9).
+   * `!` will be replaced by a random digit (2-9).
+   * (e.g. `!##-!##-####` -> 272-285-0453)
+   *
+   * @see Helpers.replaceSymbolWithNumber(format)
+   */
+  formats: string[];
+}
+
+/**
+ * Internal: A list of all keys for the PhoneNumberDefinitions.
+ */
+export const PHONE_NUMBER = allOf<keyof PhoneNumberDefinitions>()('formats');
diff --git a/src/definitions/system.ts b/src/definitions/system.ts
new file mode 100644
index 00000000000..5c9039b43d1
--- /dev/null
+++ b/src/definitions/system.ts
@@ -0,0 +1,33 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to files and the system.
+ */
+export interface SystemDefinitions {
+  /**
+   * Returns some common file paths.
+   */
+  directoryPaths: string[];
+  /**
+   * The mime type definitions with some additional information.
+   */
+  mimeTypes: { [mimeType: string]: SystemMimeTypeEntryDefinitions };
+}
+
+/**
+ * The mime type entry details.
+ */
+export interface SystemMimeTypeEntryDefinitions {
+  source?: string;
+  extensions?: string[];
+  compressible?: boolean;
+  charset?: string;
+}
+
+/**
+ * Internal: A list of all keys for the SystemDefinitions.
+ */
+export const SYSTEM = allOf<keyof SystemDefinitions>()(
+  'directoryPaths',
+  'mimeTypes'
+);
diff --git a/src/definitions/utils.ts b/src/definitions/utils.ts
new file mode 100644
index 00000000000..b7b826a1657
--- /dev/null
+++ b/src/definitions/utils.ts
@@ -0,0 +1,8 @@
+// https://stackoverflow.com/a/53395649/4573065
+export type AllOf<T> = ['Needs to be all of', T];
+
+export function allOf<T>(): <U extends T[]>(
+  ...array: U & ([T] extends [U[number]] ? unknown : AllOf<T>[])
+) => U & ([T] extends [U[number]] ? unknown : AllOf<T>[]) {
+  return (...array) => array;
+}
diff --git a/src/definitions/vehicle.ts b/src/definitions/vehicle.ts
new file mode 100644
index 00000000000..7fdc11f1de1
--- /dev/null
+++ b/src/definitions/vehicle.ts
@@ -0,0 +1,38 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to vehicles.
+ */
+export interface VehicleDefinitions {
+  /**
+   * Some types of bicycles.
+   */
+  bicycle_type: string[];
+  /**
+   * Some types of fuel (e.g. `Gasoline`).
+   */
+  fuel: string[];
+  /**
+   * Some brands of manufactures (e.g. `Tesla`).
+   */
+  manufacturer: string[];
+  /**
+   * Some names of models (e.g. `Fiesta`).
+   */
+  model: string[];
+  /**
+   * Some types of vehicles (e.g. `Minivan`).
+   */
+  type: string[];
+}
+
+/**
+ * Internal: A list of all keys for the VehicleDefinitions.
+ */
+export const VEHICLE = allOf<keyof VehicleDefinitions>()(
+  'bicycle_type',
+  'fuel',
+  'manufacturer',
+  'model',
+  'type'
+);
diff --git a/src/definitions/word.ts b/src/definitions/word.ts
new file mode 100644
index 00000000000..dcbe47dd508
--- /dev/null
+++ b/src/definitions/word.ts
@@ -0,0 +1,27 @@
+import { allOf } from './utils';
+
+/**
+ * The possible definitions related to words.
+ */
+export interface WordDefinitions {
+  adjective: string[];
+  adverb: string[];
+  conjunction: string[];
+  interjection: string[];
+  noun: string[];
+  preposition: string[];
+  verb: string[];
+}
+
+/**
+ * Internal: A list of all keys for the WordDefinitions.
+ */
+export const WORD = allOf<keyof WordDefinitions>()(
+  'adjective',
+  'adverb',
+  'conjunction',
+  'interjection',
+  'noun',
+  'preposition',
+  'verb'
+);
diff --git a/src/finance.ts b/src/finance.ts
index 719d1198e95..9a7592518b5 100644
--- a/src/finance.ts
+++ b/src/finance.ts
@@ -244,6 +244,7 @@ export class Finance {
       format = provider;
     } else {
       // Choose a random provider
+      // TODO ST-DDT 2022-01-30: #375 This is impossible to access
       if (typeof localeFormat === 'string') {
         format = localeFormat;
       } else if (typeof localeFormat === 'object') {
diff --git a/src/index.ts b/src/index.ts
index d740faea929..4d9e8438cae 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -5,7 +5,8 @@ import { Company } from './company';
 import { Database } from './database';
 import { Datatype } from './datatype';
 import { _Date } from './date';
-import type { Definitions } from './definitions';
+import type { LocaleDefinition } from './definitions';
+import { DEFINITIONS } from './definitions';
 import { Fake } from './fake';
 import { Finance } from './finance';
 import { Git } from './git';
@@ -30,171 +31,10 @@ import { Word } from './word';
 // https://github.com/microsoft/TypeScript/issues/29729#issuecomment-471566609
 type LiteralUnion<T extends U, U = string> = T | (U & { zz_IGNORE_ME?: never });
 
-export interface LocaleDefinition {
-  title: string;
-  separator?: string;
-
-  address?: Partial<{
-    building_number: any[];
-    city_name: any[];
-    city_prefix: any[];
-    city_suffix: any[];
-    city: any[];
-    country_code_alpha_3: any[];
-    country_code: any[];
-    country: any[];
-    county: any[];
-    default_country: any[];
-    direction_abbr: any[];
-    direction: any[];
-    postcode_by_state: any[];
-    postcode: any[];
-    secondary_address: any[];
-    state_abbr: any[];
-    state: any[];
-    street_address: any[];
-    street_name: any[];
-    street_suffix: any[];
-    time_zone: any[];
-  }>;
-  animal?: Partial<{
-    bear: any[];
-    bird: any[];
-    cat: any[];
-    cetacean: any[];
-    cow: any[];
-    crocodilia: any[];
-    dog: any[];
-    fish: any[];
-    horse: any[];
-    insect: any[];
-    lion: any[];
-    rabbit: any[];
-    snake: any[];
-    type: any[];
-  }>;
-  app?: Partial<{
-    author: any[];
-    name: any[];
-    version: any[];
-  }>;
-  business?: Partial<{
-    credit_card_expiry_dates: any[];
-    credit_card_numbers: any[];
-    credit_card_types: any[];
-  }>;
-  cell_phone?: Partial<{
-    formats: any[];
-  }>;
-  commerce?: Partial<{
-    color: any[];
-    department: any[];
-    product_description: any[];
-    product_name: any[];
-  }>;
-  company?: Partial<{
-    adjective: any[];
-    bs_adjective: any[];
-    bs_noun: any[];
-    bs_verb: any[];
-    descriptor: any[];
-    name: any[];
-    noun: any[];
-    suffix: any[];
-  }>;
-  database?: Partial<{
-    collation: any[];
-    column: any[];
-    engine: any[];
-    type: any[];
-  }>;
-  date?: Partial<{
-    month: any[];
-    weekday: any[];
-  }>;
-  finance?: Partial<{
-    account_type: any[];
-    credit_card: any[];
-    currency: any[];
-    transaction_type: any[];
-  }>;
-  hacker?: Partial<{
-    abbreviation: any[];
-    adjective: any[];
-    ingverb: any[];
-    noun: any[];
-    phrase: any[];
-    verb: any[];
-  }>;
-  internet?: Partial<{
-    avatar_uri: any[];
-    domain_suffix: any[];
-    example_email: any[];
-    free_email: any[];
-  }>;
-  lorem?: Partial<{
-    supplemental: any[];
-    words: any[];
-  }>;
-  music?: Partial<{
-    genre: any[];
-  }>;
-  name?: Partial<{
-    binary_gender: string[];
-    female_first_name: string[];
-    female_last_name: string[];
-    female_middle_name: string[];
-    female_prefix: string[];
-    first_name: string[];
-    gender: string[];
-    last_name: string[];
-    male_first_name: string[];
-    male_last_name: string[];
-    male_middle_name: string[];
-    male_prefix: string[];
-    name: string[];
-    prefix: string[];
-    suffix: string[];
-    title: {
-      descriptor?: string[];
-      job: string[];
-      level?: string[];
-    };
-  }>;
-  phone_number?: Partial<{
-    formats: any[];
-  }>;
-  system?: Partial<{
-    directoryPaths: any[];
-    mimeTypes: any[];
-  }>;
-  team?: Partial<{
-    creature: any[];
-    name: any[];
-  }>;
-  vehicle?: Partial<{
-    bicycle: any[];
-    fuel: any[];
-    manufacturer: any[];
-    model: any[];
-    type: any[];
-  }>;
-  word?: Partial<{
-    adjective: any[];
-    adverb: any[];
-    conjunction: any[];
-    interjection: any[];
-    noun: any[];
-    preposition: any[];
-    verb: any[];
-  }>;
-  [group: string]: any;
-}
-
 export type UsableLocale = LiteralUnion<KnownLocale>;
 export type UsedLocales = Partial<Record<UsableLocale, LocaleDefinition>>;
 
-export type { Definitions };
+export type { LocaleDefinition };
 
 export interface FakerOptions {
   locales?: UsedLocales;
@@ -202,145 +42,13 @@ export interface FakerOptions {
   localeFallback?: UsableLocale;
 }
 
-export interface DefinitionTypes {
-  readonly name: string[];
-  readonly address: string[];
-  readonly animal: string[];
-  readonly company: string[];
-  readonly lorem: string[];
-  readonly hacker: string[];
-  readonly phone_number: string[];
-  readonly finance: string[];
-  readonly internet: string[];
-  readonly commerce: string[];
-  readonly database: string[];
-  readonly system: string[];
-  readonly date: string[];
-  readonly vehicle: string[];
-  readonly music: string[];
-  readonly word: string[];
-  readonly title: string | string[];
-  readonly separator: string | string[];
-}
-
 export class Faker {
   locales: UsedLocales;
   locale: UsableLocale;
   localeFallback: UsableLocale;
 
-  // @ts-expect-error: will be lazy filled by constructor
-  readonly definitions: Definitions = {};
-  private readonly definitionTypes: DefinitionTypes = {
-    name: [
-      'first_name',
-      'last_name',
-      'prefix',
-      'suffix',
-      'binary_gender',
-      'gender',
-      'title',
-      'male_prefix',
-      'female_prefix',
-      'male_first_name',
-      'female_first_name',
-      'male_middle_name',
-      'female_middle_name',
-      'male_last_name',
-      'female_last_name',
-    ],
-    address: [
-      'city_name',
-      'city_prefix',
-      'city_suffix',
-      'street_suffix',
-      'county',
-      'country',
-      'country_code',
-      'country_code_alpha_3',
-      'state',
-      'state_abbr',
-      'street_prefix',
-      'postcode',
-      'postcode_by_state',
-      'direction',
-      'direction_abbr',
-      'time_zone',
-    ],
-    animal: [
-      'dog',
-      'cat',
-      'snake',
-      'bear',
-      'lion',
-      'cetacean',
-      'insect',
-      'crocodilia',
-      'cow',
-      'bird',
-      'fish',
-      'rabbit',
-      'horse',
-      'type',
-    ],
-    company: [
-      'adjective',
-      'noun',
-      'descriptor',
-      'bs_adjective',
-      'bs_noun',
-      'bs_verb',
-      'suffix',
-    ],
-    lorem: ['words'],
-    hacker: ['abbreviation', 'adjective', 'noun', 'verb', 'ingverb', 'phrase'],
-    phone_number: ['formats'],
-    finance: [
-      'account_type',
-      'transaction_type',
-      'currency',
-      'iban',
-      'credit_card',
-    ],
-    internet: [
-      'avatar_uri',
-      'domain_suffix',
-      'free_email',
-      'example_email',
-      'password',
-    ],
-    commerce: [
-      'color',
-      'department',
-      'product_name',
-      'price',
-      'categories',
-      'product_description',
-    ],
-    database: ['collation', 'column', 'engine', 'type'],
-    system: ['mimeTypes', 'directoryPaths'],
-    date: ['month', 'weekday'],
-    vehicle: [
-      'vehicle',
-      'manufacturer',
-      'model',
-      'type',
-      'fuel',
-      'vin',
-      'color',
-    ],
-    music: ['genre'],
-    word: [
-      'adjective',
-      'adverb',
-      'conjunction',
-      'interjection',
-      'noun',
-      'preposition',
-      'verb',
-    ],
-    title: '',
-    separator: '',
-  };
+  // Will be lazy init
+  readonly definitions: LocaleDefinition = {} as LocaleDefinition;
 
   seedValue?: any[] | any;
 
@@ -381,30 +89,26 @@ export class Faker {
     this.locale = this.locale || opts.locale || 'en';
     this.localeFallback = this.localeFallback || opts.localeFallback || 'en';
 
-    this.loadDefinitions(this.definitionTypes);
+    this.loadDefinitions();
   }
 
   /**
    * Load the definitions contained in the locales file for the given types
-   *
-   * @param types
    */
-  private loadDefinitions(types: DefinitionTypes): void {
+  private loadDefinitions(): void {
     // TODO @Shinigami92 2022-01-11: Find a way to load this even more dynamically
     // In a way so that we don't accidentally miss a definition
-    Object.keys(types).forEach((t: keyof DefinitionTypes) => {
+    Object.entries(DEFINITIONS).forEach(([t, v]) => {
       if (typeof this.definitions[t] === 'undefined') {
         this.definitions[t] = {};
       }
 
-      if (typeof types[t] === 'string') {
-        this.definitions[t] = types[t];
+      if (typeof v === 'string') {
+        this.definitions[t] = v;
         return;
       }
 
-      // TODO @Shinigami92 2022-01-11: We may have a bug here for the keys 'title' and 'separator'
-      // @ts-expect-error
-      types[t].forEach((p) => {
+      v.forEach((p) => {
         Object.defineProperty(this.definitions[t], p, {
           get: () => {
             if (
diff --git a/src/locales/el/credit_card/index.ts b/src/locales/el/credit_card/index.ts
index 3ed856dc133..92cf1e689f1 100644
--- a/src/locales/el/credit_card/index.ts
+++ b/src/locales/el/credit_card/index.ts
@@ -1,10 +1,11 @@
+import type { FinanceDefinitions } from '../../../definitions';
 import american_express from './american_express';
 import discover from './discover';
 import maestro from './maestro';
 import mastercard from './mastercard';
 import visa from './visa';
 
-const credit_card: any = {
+const credit_card: FinanceDefinitions['credit_card'] = {
   american_express,
   discover,
   maestro,
diff --git a/src/locales/el/finance/index.ts b/src/locales/el/finance/index.ts
index d899702fd31..76e0fa8d062 100644
--- a/src/locales/el/finance/index.ts
+++ b/src/locales/el/finance/index.ts
@@ -1,8 +1,9 @@
+import type { FinanceDefinitions } from '../../../definitions';
 import account_type from './account_type';
 import currency from './currency';
 import transaction_type from './transaction_type';
 
-const finance: any = {
+const finance: Partial<FinanceDefinitions> = {
   account_type,
   currency,
   transaction_type,
diff --git a/src/locales/el/hacker/index.ts b/src/locales/el/hacker/index.ts
index 35032f5227c..28143c2bd80 100644
--- a/src/locales/el/hacker/index.ts
+++ b/src/locales/el/hacker/index.ts
@@ -1,9 +1,10 @@
+import type { HackerDefinitions } from '../../../definitions';
 import abbreviation from './abbreviation';
 import adjective from './adjective';
 import noun from './noun';
 import verb from './verb';
 
-const hacker: any = {
+const hacker: Partial<HackerDefinitions> = {
   abbreviation,
   adjective,
   noun,
diff --git a/src/locales/en/address/index.ts b/src/locales/en/address/index.ts
index d0677de66cc..27c071aa886 100644
--- a/src/locales/en/address/index.ts
+++ b/src/locales/en/address/index.ts
@@ -1,3 +1,4 @@
+import type { AddressDefinitions } from '../../../definitions';
 import building_number from './building_number';
 import city from './city';
 import city_name from './city_name';
@@ -20,28 +21,38 @@ import street_name from './street_name';
 import street_suffix from './street_suffix';
 import time_zone from './time_zone';
 
-const address: any = {
-  building_number,
+const address = {
+  postcode,
+  postcode_by_state,
+
   city,
   city_name,
   city_prefix,
   city_suffix,
+
   country,
-  country_code,
-  country_code_alpha_3,
+  state,
+  state_abbr,
   county,
-  default_country,
+
   direction,
   direction_abbr,
-  postcode,
-  postcode_by_state,
+
+  // street_prefix
+  street_suffix,
+
   secondary_address,
-  state,
-  state_abbr,
+
+  country_code,
+  country_code_alpha_3,
+
+  time_zone,
+
+  // Extra
   street_address,
   street_name,
-  street_suffix,
-  time_zone,
-};
+  default_country,
+  building_number,
+} as Partial<AddressDefinitions>;
 
 export default address;
diff --git a/src/locales/en/animal/index.ts b/src/locales/en/animal/index.ts
index f576b998579..33625a81f44 100644
--- a/src/locales/en/animal/index.ts
+++ b/src/locales/en/animal/index.ts
@@ -1,3 +1,4 @@
+import type { AnimalDefinitions } from '../../../definitions';
 import bear from './bear';
 import bird from './bird';
 import cat from './cat';
@@ -13,7 +14,7 @@ import rabbit from './rabbit';
 import snake from './snake';
 import type from './type';
 
-const animal: any = {
+const animal: AnimalDefinitions = {
   bear,
   bird,
   cat,
diff --git a/src/locales/en/commerce/index.ts b/src/locales/en/commerce/index.ts
index 74ccad9a532..30ab7e1ee56 100644
--- a/src/locales/en/commerce/index.ts
+++ b/src/locales/en/commerce/index.ts
@@ -1,9 +1,10 @@
+import type { CommerceDefinitions } from '../../../definitions';
 import color from './color';
 import department from './department';
 import product_description from './product_description';
 import product_name from './product_name';
 
-const commerce: any = {
+const commerce: CommerceDefinitions = {
   color,
   department,
   product_description,
diff --git a/src/locales/en/company/index.ts b/src/locales/en/company/index.ts
index 9c2343931ad..82326134396 100644
--- a/src/locales/en/company/index.ts
+++ b/src/locales/en/company/index.ts
@@ -1,3 +1,4 @@
+import type { CompanyDefinitions } from '../../../definitions';
 import adjective from './adjective';
 import bs_adjective from './bs_adjective';
 import bs_noun from './bs_noun';
@@ -7,15 +8,18 @@ import name from './name';
 import noun from './noun';
 import suffix from './suffix';
 
-const company: any = {
-  adjective,
+const company = {
   bs_adjective,
   bs_noun,
   bs_verb,
+
+  adjective,
   descriptor,
-  name,
   noun,
+
   suffix,
-};
+
+  name,
+} as CompanyDefinitions;
 
 export default company;
diff --git a/src/locales/en/database/index.ts b/src/locales/en/database/index.ts
index 8be270761e9..44774db2121 100644
--- a/src/locales/en/database/index.ts
+++ b/src/locales/en/database/index.ts
@@ -1,9 +1,10 @@
+import type { DatabaseDefinitions } from '../../../definitions';
 import collation from './collation';
 import column from './column';
 import engine from './engine';
 import type from './type';
 
-const database: any = {
+const database: DatabaseDefinitions = {
   collation,
   column,
   engine,
diff --git a/src/locales/en/date/index.ts b/src/locales/en/date/index.ts
index 35b1df67c7d..e722b683f7b 100644
--- a/src/locales/en/date/index.ts
+++ b/src/locales/en/date/index.ts
@@ -1,7 +1,8 @@
+import type { DateDefinitions } from '../../../definitions';
 import month from './month';
 import weekday from './weekday';
 
-const date: any = {
+const date: DateDefinitions = {
   month,
   weekday,
 };
diff --git a/src/locales/en/finance/credit_card/index.ts b/src/locales/en/finance/credit_card/index.ts
index 47b74b5a06c..08f33e9cbc9 100644
--- a/src/locales/en/finance/credit_card/index.ts
+++ b/src/locales/en/finance/credit_card/index.ts
@@ -1,3 +1,4 @@
+import type { FinanceDefinitions } from '../../../../definitions';
 import american_express from './american_express';
 import diners_club from './diners_club';
 import discover from './discover';
@@ -10,7 +11,7 @@ import solo from './solo';
 import switch_ from './switch';
 import visa from './visa';
 
-const credit_card: any = {
+const credit_card: FinanceDefinitions['credit_card'] = {
   american_express,
   diners_club,
   discover,
diff --git a/src/locales/en/finance/index.ts b/src/locales/en/finance/index.ts
index 969746b0687..004d53143cb 100644
--- a/src/locales/en/finance/index.ts
+++ b/src/locales/en/finance/index.ts
@@ -1,9 +1,10 @@
+import type { FinanceDefinitions } from '../../../definitions';
 import account_type from './account_type';
 import credit_card from './credit_card';
 import currency from './currency';
 import transaction_type from './transaction_type';
 
-const finance: any = {
+const finance: FinanceDefinitions = {
   account_type,
   credit_card,
   currency,
diff --git a/src/locales/en/hacker/index.ts b/src/locales/en/hacker/index.ts
index 959b7e0a14c..196657a8320 100644
--- a/src/locales/en/hacker/index.ts
+++ b/src/locales/en/hacker/index.ts
@@ -1,3 +1,4 @@
+import type { HackerDefinitions } from '../../../definitions';
 import abbreviation from './abbreviation';
 import adjective from './adjective';
 import ingverb from './ingverb';
@@ -5,7 +6,7 @@ import noun from './noun';
 import phrase from './phrase';
 import verb from './verb';
 
-const hacker: any = {
+const hacker: HackerDefinitions = {
   abbreviation,
   adjective,
   ingverb,
diff --git a/src/locales/en/internet/index.ts b/src/locales/en/internet/index.ts
index 028fd227691..a1788c66178 100644
--- a/src/locales/en/internet/index.ts
+++ b/src/locales/en/internet/index.ts
@@ -1,13 +1,14 @@
+import type { InternetDefinitions } from '../../../definitions';
 import avatar_uri from './avatar_uri';
 import domain_suffix from './domain_suffix';
 import example_email from './example_email';
 import free_email from './free_email';
 
-const internet: any = {
+const internet = {
   avatar_uri,
   domain_suffix,
   example_email,
   free_email,
-};
+} as InternetDefinitions;
 
 export default internet;
diff --git a/src/locales/en/lorem/index.ts b/src/locales/en/lorem/index.ts
index 62962376cd4..9f1838e169e 100644
--- a/src/locales/en/lorem/index.ts
+++ b/src/locales/en/lorem/index.ts
@@ -1,9 +1,10 @@
+import type { LoremDefinitions } from '../../../definitions';
 import supplemental from './supplemental';
 import words from './words';
 
-const lorem: any = {
+const lorem = {
   supplemental,
   words,
-};
+} as LoremDefinitions;
 
 export default lorem;
diff --git a/src/locales/en/music/index.ts b/src/locales/en/music/index.ts
index 54b9163ea41..3347664de77 100644
--- a/src/locales/en/music/index.ts
+++ b/src/locales/en/music/index.ts
@@ -1,6 +1,7 @@
+import type { MusicDefinitions } from '../../../definitions';
 import genre from './genre';
 
-const music: any = {
+const music: MusicDefinitions = {
   genre,
 };
 
diff --git a/src/locales/en/name/index.ts b/src/locales/en/name/index.ts
index 6e21934a33d..8241b4ad716 100644
--- a/src/locales/en/name/index.ts
+++ b/src/locales/en/name/index.ts
@@ -1,3 +1,4 @@
+import type { NameDefinitions } from '../../../definitions';
 import binary_gender from './binary_gender';
 import female_first_name from './female_first_name';
 import first_name from './first_name';
@@ -9,16 +10,22 @@ import prefix from './prefix';
 import suffix from './suffix';
 import title from './title';
 
-const name: any = {
+const name: NameDefinitions = {
   binary_gender,
-  female_first_name,
-  first_name,
   gender,
-  last_name,
-  male_first_name,
-  name: name_,
+
   prefix,
+
+  first_name,
+  female_first_name,
+  male_first_name,
+
+  last_name,
+
   suffix,
+
+  name: name_,
+
   title,
 };
 
diff --git a/src/locales/en/name/title.ts b/src/locales/en/name/title.ts
index b18b6004c1b..ec599841aa0 100644
--- a/src/locales/en/name/title.ts
+++ b/src/locales/en/name/title.ts
@@ -1,4 +1,6 @@
-export default {
+import type { NameTitleDefinitions } from '../../../definitions';
+
+const title: NameTitleDefinitions = {
   descriptor: [
     'Lead',
     'Senior',
@@ -90,3 +92,5 @@ export default {
     'Strategist',
   ],
 };
+
+export default title;
diff --git a/src/locales/en/phone_number/index.ts b/src/locales/en/phone_number/index.ts
index f760b9e1550..6b8f73b0266 100644
--- a/src/locales/en/phone_number/index.ts
+++ b/src/locales/en/phone_number/index.ts
@@ -1,6 +1,7 @@
+import type { PhoneNumberDefinitions } from '../../../definitions';
 import formats from './formats';
 
-const phone_number: any = {
+const phone_number: PhoneNumberDefinitions = {
   formats,
 };
 
diff --git a/src/locales/en/system/index.ts b/src/locales/en/system/index.ts
index 3fde96086c0..c873d9d702a 100644
--- a/src/locales/en/system/index.ts
+++ b/src/locales/en/system/index.ts
@@ -1,7 +1,8 @@
+import type { SystemDefinitions } from '../../../definitions';
 import directoryPaths from './directoryPaths';
 import mimeTypes from './mimeTypes';
 
-const system: any = {
+const system: SystemDefinitions = {
   directoryPaths,
   mimeTypes,
 };
diff --git a/src/locales/en/vehicle/index.ts b/src/locales/en/vehicle/index.ts
index f48d68b37d1..01ecc1c034f 100644
--- a/src/locales/en/vehicle/index.ts
+++ b/src/locales/en/vehicle/index.ts
@@ -1,15 +1,16 @@
+import type { VehicleDefinitions } from '../../../definitions';
 import bicycle from './bicycle';
 import fuel from './fuel';
 import manufacturer from './manufacturer';
 import model from './model';
 import type_ from './type';
 
-const vehicle: any = {
+const vehicle = {
   bicycle,
   fuel,
   manufacturer,
   model,
   type: type_,
-};
+} as Partial<VehicleDefinitions>;
 
 export default vehicle;
diff --git a/src/locales/en/word/index.ts b/src/locales/en/word/index.ts
index 7fed2b4375c..8f76f579b7b 100644
--- a/src/locales/en/word/index.ts
+++ b/src/locales/en/word/index.ts
@@ -1,3 +1,4 @@
+import type { WordDefinitions } from '../../../definitions';
 import adjective from './adjective';
 import adverb from './adverb';
 import conjunction from './conjunction';
@@ -6,7 +7,7 @@ import noun from './noun';
 import preposition from './preposition';
 import verb from './verb';
 
-const word: any = {
+const word: WordDefinitions = {
   adjective,
   adverb,
   conjunction,
diff --git a/src/locales/fa/finance/credit_card/index.ts b/src/locales/fa/finance/credit_card/index.ts
index a05f43510f4..7a1430a4ac3 100644
--- a/src/locales/fa/finance/credit_card/index.ts
+++ b/src/locales/fa/finance/credit_card/index.ts
@@ -1,7 +1,8 @@
+import type { FinanceDefinitions } from '../../../../definitions';
 import mastercard from './mastercard';
 import visa from './visa';
 
-const credit_card: any = {
+const credit_card: FinanceDefinitions['credit_card'] = {
   mastercard,
   visa,
 };
diff --git a/src/locales/fa/finance/index.ts b/src/locales/fa/finance/index.ts
index 969746b0687..004d53143cb 100644
--- a/src/locales/fa/finance/index.ts
+++ b/src/locales/fa/finance/index.ts
@@ -1,9 +1,10 @@
+import type { FinanceDefinitions } from '../../../definitions';
 import account_type from './account_type';
 import credit_card from './credit_card';
 import currency from './currency';
 import transaction_type from './transaction_type';
 
-const finance: any = {
+const finance: FinanceDefinitions = {
   account_type,
   credit_card,
   currency,
diff --git a/src/locales/nl/hacker/index.ts b/src/locales/nl/hacker/index.ts
index 34dc68f20d0..12c95cf77dc 100644
--- a/src/locales/nl/hacker/index.ts
+++ b/src/locales/nl/hacker/index.ts
@@ -1,9 +1,10 @@
+import type { HackerDefinitions } from '../../../definitions';
 import adjective from './adjective';
 import noun from './noun';
 import phrase from './phrase';
 import verb from './verb';
 
-const hacker: any = {
+const hacker: Partial<HackerDefinitions> = {
   adjective,
   noun,
   phrase,
diff --git a/src/locales/ru/hacker/index.ts b/src/locales/ru/hacker/index.ts
index 959b7e0a14c..d19ca4b25d0 100644
--- a/src/locales/ru/hacker/index.ts
+++ b/src/locales/ru/hacker/index.ts
@@ -1,3 +1,4 @@
+import type { HackerDefinitions } from '../../../definitions';
 import abbreviation from './abbreviation';
 import adjective from './adjective';
 import ingverb from './ingverb';
@@ -5,7 +6,7 @@ import noun from './noun';
 import phrase from './phrase';
 import verb from './verb';
 
-const hacker: any = {
+const hacker: Partial<HackerDefinitions> = {
   abbreviation,
   adjective,
   ingverb,
diff --git a/src/lorem.ts b/src/lorem.ts
index 9368ec019fa..afbc6df36e6 100644
--- a/src/lorem.ts
+++ b/src/lorem.ts
@@ -24,7 +24,7 @@ export class Lorem {
    */
   word(length?: number): string {
     const hasRightLength = (word: string) => word.length === length;
-    let properLengthWords: string[];
+    let properLengthWords: readonly string[];
     if (typeof length === 'undefined') {
       properLengthWords = this.faker.definitions.lorem.words;
     } else {
diff --git a/src/name.ts b/src/name.ts
index d00094e24b3..74c8e522e35 100644
--- a/src/name.ts
+++ b/src/name.ts
@@ -110,11 +110,11 @@ export class Name {
       }
       if (gender === 0) {
         return this.faker.random.arrayElement(
-          this.faker.locales[this.faker.locale].name.male_middle_name
+          this.faker.definitions.name.male_middle_name
         );
       } else {
         return this.faker.random.arrayElement(
-          this.faker.locales[this.faker.locale].name.female_middle_name
+          this.faker.definitions.name.female_middle_name
         );
       }
     }