diff --git a/src/book-viewer.js b/src/book-viewer.js
index 0611b26b..2e2735ef 100644
--- a/src/book-viewer.js
+++ b/src/book-viewer.js
@@ -19,6 +19,7 @@ import './navbar.js'
 import {
     AnnotationPopover, AnnotationModel, BookmarkModel, exportAnnotations,
 } from './annotations.js'
+import { SelectionPopover } from './selection-tools.js'
 import { ImageViewer } from './image-viewer.js'
 import { makeBookInfoWindow } from './book-info.js'
 import { getURIStore, getBookList } from './library.js'
@@ -577,12 +578,6 @@ GObject.registerClass({
     grab_focus() { return this.#webView.grab_focus() }
 })
 
-const SelectionPopover = GObject.registerClass({
-    GTypeName: 'FoliateSelectionPopover',
-    Template: pkg.moduleuri('ui/selection-popover.ui'),
-}, class extends Gtk.PopoverMenu {
-})
-
 const autohide = (revealer, shouldStayVisible) => {
     const show = () => revealer.reveal_child = true
     const hide = () => revealer.reveal_child = false
@@ -951,7 +946,7 @@ export const BookViewer = GObject.registerClass({
             this.#data.storage.set('lastLocation', cfi)
         }
     }
-    #showSelection({ type, value, text, pos: { point, dir } }) {
+    #showSelection({ type, value, text, lang, pos: { point, dir } }) {
         if (type === 'annotation') return new Promise(resolve => {
             const annotation = this.#data.annotations.get(value)
             const popover = utils.connect(new AnnotationPopover({ annotation }), {
@@ -991,10 +986,14 @@ export const BookViewer = GObject.registerClass({
                 },
                 'print': () => resolve('print'),
             }))
-            // it seems `closed` is emitted before the actions are run
-            // so it needs the timeout
-            popover.connect('closed', () => setTimeout(() =>
-                resolved ? null : resolve(), 0))
+            utils.connect(popover, {
+                'show-popover': (_, popover) =>
+                    this._view.showPopover(popover, point, dir),
+                'run-tool': () => ({ text, lang }),
+                // it seems `closed` is emitted before the actions are run
+                // so it needs the timeout
+                'closed': () => setTimeout(() => resolved ? null : resolve(), 0),
+            })
             this._view.showPopover(popover, point, dir)
         })
     }
diff --git a/src/reader/reader.js b/src/reader/reader.js
index c5f87de0..0203c34f 100644
--- a/src/reader/reader.js
+++ b/src/reader/reader.js
@@ -33,6 +33,12 @@ const getSelectionRange = doc => {
     return range
 }
 
+const getLang = el => {
+    const lang = el.lang || el?.getAttributeNS?.('http://www.w3.org/XML/1998/namespace', 'lang')
+    if (lang) return lang
+    if (el.parentElement) return getLang(el.parentElement)
+}
+
 const blobToBase64 = blob => new Promise(resolve => {
     const reader = new FileReader()
     reader.readAsDataURL(blob)
@@ -363,7 +369,8 @@ class Reader {
             if (!range) return
             const pos = getPosition(range)
             const value = this.view.getCFI(index, range)
-            this.#showSelection({ range, value, pos })
+            const lang = getLang(range.commonAncestorContainer)
+            this.#showSelection({ range, lang, value, pos })
         })
 
         if (!this.view.isFixedLayout)
@@ -386,9 +393,9 @@ class Reader {
                     this.#showSelection({ range, value, pos })
             })
     }
-    #showSelection({ range, value, pos }) {
+    #showSelection({ range, lang, value, pos }) {
         const text = range.toString()
-        globalThis.showSelection({ type: 'selection', text, value, pos })
+        globalThis.showSelection({ type: 'selection', text, lang, value, pos })
             .then(action => {
                 if (action === 'copy') getHTML(range).then(html =>
                     emit({ type: 'selection', action, text, html }))
diff --git a/src/selection-tools.js b/src/selection-tools.js
new file mode 100644
index 00000000..e29b0af4
--- /dev/null
+++ b/src/selection-tools.js
@@ -0,0 +1,232 @@
+import Gtk from 'gi://Gtk'
+import Gio from 'gi://Gio'
+import GObject from 'gi://GObject'
+import WebKit from 'gi://WebKit'
+import Gdk from 'gi://Gdk'
+import { gettext as _ } from 'gettext'
+
+import * as utils from './utils.js'
+import { WebView } from './webview.js'
+
+const tools = {
+    'dictionary': {
+        label: _('Dictionary'),
+        run: ({ text, lang }) => {
+            const { language } = new Intl.Locale(lang)
+            return `
+<base href="https://en.wiktionary.org/wiki/Wiktionary:Main_Page">
+<style>
+html, body {
+    color-scheme: light dark;
+    font: menu;
+}
+a:any-link {
+    color: highlight;
+}
+h2 {
+    font-size: smaller;
+}
+ul, ol {
+    padding-inline-start: 2em;
+}
+ul {
+    margin: .5em 0;
+    font-style: italic;
+    opacity: .75;
+    font-size: smaller;
+    list-style: none;
+}
+h1 {
+    font-size: larger;
+    padding-inline-end: 1em;
+    display: inline;
+}
+hgroup p {
+    font-size: smaller;
+    display: inline;
+}
+footer {
+    font-size: smaller;
+    opacity: .6;
+    display: none;
+}
+[data-state="loaded"] footer {
+    display: block;
+}
+[data-state="error"] main {
+    display: flex;
+    position: absolute;
+    inset: 0;
+    width: 100%;
+    height: 100%;
+    text-align: center;
+    justify-content: center;
+    align-items: center;
+}
+</style>
+<main></main>
+<footer><p>${_('From <a id="link">Wiktionary</a>, released under the <a href="https://creativecommons.org/licenses/by-sa/4.0/">CC BY-SA License</a>.')}</footer>
+<script>
+const main = document.querySelector('main')
+const footer = document.querySelector('footer')
+const link = document.querySelector('#link')
+const wiktionary = (word, language, languageName) => {
+    document.body.dataset.state = 'loading'
+    return fetch('https://en.wiktionary.org/api/rest_v1/page/definition/' + encodeURI(word))
+        .then(res => res.ok ? res.json() : Promise.reject(new Error()))
+        .then(json => {
+            const results = language ? json[language]
+                : languageName ? Object.values(json)
+                    .find(x => x.some(x => x.language === languageName))
+                : json['en']
+            const hgroup = document.createElement('hgroup')
+            const h1 = document.createElement('h1')
+            h1.innerText = word
+            const p = document.createElement('p')
+            p.innerText = results[0].language
+            hgroup.append(h1, p)
+            main.append(hgroup)
+            for (const { partOfSpeech, definitions } of results) {
+                const h2 = document.createElement('h2')
+                h2.innerText = partOfSpeech
+                const ol = document.createElement('ol')
+                main.append(h2, ol)
+                for (const { definition, examples } of definitions) {
+                    const li = document.createElement('li')
+                    li.innerHTML = definition
+                    ol.append(li)
+                    const ul = document.createElement('ul')
+                    li.append(ul)
+                    if (examples) for (const example of examples) {
+                        const li = document.createElement('li')
+                        li.innerHTML = example
+                        ul.append(li)
+                    }
+                }
+            }
+            link.href = '/wiki/' + word
+            document.body.dataset.state = 'loaded'
+        })
+        .catch(e => {
+            console.error(e)
+            const lower = word.toLocaleLowerCase(language)
+            if (lower !== word) return wiktionary(lower, language)
+            else {
+                const div = document.createElement('div')
+                const h1 = document.createElement('h1')
+                h1.innerText = decodeURIComponent("${encodeURIComponent(_('No Definitions Found'))}")
+                const p = document.createElement('p')
+                p.innerHTML = \`<a href="https://en.wiktionary.org/w/index.php?search=${encodeURIComponent(text)}">${_('Search on Wiktionary')}</a>\`
+                div.append(h1, p)
+                main.append(div)
+                document.body.dataset.state = 'error'
+            }
+        })
+}
+
+// see https://en.wiktionary.org/wiki/Wiktionary:Namespace
+const wikiNamespaces = [
+    'Media', 'Special', 'Talk', 'User', 'Wiktionary', 'File', 'MediaWiki',
+    'Template', 'Help', 'Category',
+    'Summary', 'Appendix', 'Concordance', 'Index', 'Rhymes', 'Transwiki',
+    'Thesaurus', 'Citations', 'Sign',
+]
+
+main.addEventListener('click', e => {
+    const { target } = e
+    if (target.tagName === 'A') {
+        const href = target.getAttribute('href')
+        if (href.startsWith('/wiki/')) {
+            const [word, languageName] = href.replace('/wiki/', '').split('#')
+            if (wikiNamespaces.every(namespace => !word.startsWith(namespace + ':')
+            && !word.startsWith(namespace + '_talk:'))) {
+                e.preventDefault()
+                main.replaceChildren()
+                wiktionary(word.replaceAll('_', ' '), null, languageName)
+            }
+        }
+    }
+})
+
+wiktionary(decodeURIComponent("${encodeURIComponent(text)}"),
+    decodeURIComponent("${encodeURIComponent(language)}"))
+</script>`
+        },
+    },
+}
+
+const SelectionToolPopover = GObject.registerClass({
+    GTypeName: 'FoliateSelectionToolPopover',
+}, class extends Gtk.Popover {
+    #webView = utils.connect(new WebView({
+        settings: new WebKit.Settings({
+            enable_write_console_messages_to_stdout: true,
+            enable_back_forward_navigation_gestures: false,
+            enable_hyperlink_auditing: false,
+            enable_html5_database: false,
+            enable_html5_local_storage: false,
+        }),
+    }), {
+        'decide-policy': (_, decision, type) => {
+            switch (type) {
+                case WebKit.PolicyDecisionType.NAVIGATION_ACTION:
+                case WebKit.PolicyDecisionType.NEW_WINDOW_ACTION: {
+                    const { uri } = decision.navigation_action.get_request()
+                    if (!uri.startsWith('foliate:')) {
+                        decision.ignore()
+                        Gtk.show_uri(null, uri, Gdk.CURRENT_TIME)
+                        return true
+                    }
+                }
+            }
+        },
+    })
+    constructor(params) {
+        super(params)
+        Object.assign(this, {
+            width_request: 300,
+            height_request: 300,
+        })
+        this.child = this.#webView
+        this.#webView.set_background_color(new Gdk.RGBA())
+    }
+    load(html) {
+        this.#webView.loadHTML(html, 'foliate:selection-tool')
+            .then(() => this.#webView.opacity = 1)
+            .catch(e => console.error(e))
+    }
+})
+
+const getSelectionToolPopover = utils.memoize(() => new SelectionToolPopover())
+
+export const SelectionPopover = GObject.registerClass({
+    GTypeName: 'FoliateSelectionPopover',
+    Template: pkg.moduleuri('ui/selection-popover.ui'),
+    Signals: {
+        'show-popover': { param_types: [Gtk.Popover.$gtype] },
+        'run-tool': { return_type: GObject.TYPE_JSOBJECT },
+    },
+}, class extends Gtk.PopoverMenu {
+    constructor(params) {
+        super(params)
+        const model = this.menu_model
+        const section = new Gio.Menu()
+        model.insert_section(1, null, section)
+
+        const group = new Gio.SimpleActionGroup()
+        this.insert_action_group('selection-tools', group)
+
+        for (const [name, tool] of Object.entries(tools)) {
+            const action = new Gio.SimpleAction({ name })
+            action.connect('activate', () => {
+                const popover = getSelectionToolPopover()
+                Promise.resolve(tool.run(this.emit('run-tool')))
+                    .then(x => popover.load(x))
+                    .catch(e => console.error(e))
+                this.emit('show-popover', popover)
+            })
+            group.add_action(action)
+            section.append(tool.label, `selection-tools.${name}`)
+        }
+    }
+})
diff --git a/src/ui/selection-popover.ui b/src/ui/selection-popover.ui
index cc16680d..773f968a 100644
--- a/src/ui/selection-popover.ui
+++ b/src/ui/selection-popover.ui
@@ -19,20 +19,6 @@
       <attribute name="verb-icon">edit-find-symbolic</attribute>
     </item>
   </section>
-  <section>
-    <item>
-      <attribute name="label" translatable="yes">Dictionary</attribute>
-      <attribute name="action">selection.dictionary</attribute>
-    </item>
-    <item>
-      <attribute name="label" translatable="yes">Wikipedia</attribute>
-      <attribute name="action">selection.wikipedia</attribute>
-    </item>
-    <item>
-      <attribute name="label" translatable="yes">Translate</attribute>
-      <attribute name="action">selection.translate</attribute>
-    </item>
-  </section>
   <section>
     <item>
       <attribute name="label" translatable="yes">Speak</attribute>