Dictionary Anywhere
View definitions easily as you browse the web. Double-click any word to view its definition in a small pop-up bubble. It also supports Spanish, German, French language alongside English. Enjoy Reading Uninterrupted!!!.
41,944 users
English (US) Dictionary
English (US) dictionary based on the official Mozilla dictionary.
125,038 users
French spelling dictionary
Spelling dictionary for the French language.
298,076 users
English United States Dictionary
English United States (en-US) Dictionary as shipped with Firefox 115 ESR.
394,867 users
Hungarian Dictionary
This extension is based on László Németh's Hungarian Dictionary
20,594 users
Mouse Dictionary
Super fast dictionary
3,863 users
British English Dictionary (Marco Pinto)
A fork of Mark Tyndall's add-on, based on David Bartlett's British Dictionary R1.19 for Firefox, Thunderbird and SeaMonkey. V3.3.1 has 140 000+ new words and also fixes.
214,251 users
Bulgarian Dictionary
Bulgarian spellchecking...
16,647 users
Spanish (Mexico) Dictionary
Spanish (Mexico) spell checker dictionary
12,944 users
Canadian English Dictionary
For some reason, Mozilla doesn't have a Canadian localization team, but I know that even the British dictionary doesn't quite cut it for the truly patriotic.
28,789 users
British-English Dictionary (GB)
A strict British-English spell checker dictionary for Firefox, Thunderbird and SeaMonkey. This dictionary only includes words conforming to the preferred standard of British-English spelling.
24,107 users
ImTranslator: Translator, Dictionary, TTS
COMPLETELY REDESIGNED TRANSLATOR FOR FIREFOX ImTranslator translates text, words, webpages between more than 100 languages. NEW: Inline Translator, Dictionary, access to Google Translate, Microsoft Translator. Unique on the fly localization.
136,945 users
English (Australian) Dictionary
Australian English Dictionary for Mozilla applications.
13,295 users
Arabic spell-checking dictionary
Arabic spell-checking dictionary for Firefox 3 and Thunderbird 3 from Ayaspell.
24,802 users
British English Dictionary
British English Dictionary R1.19 for Firefox, Thunderbird and SeaMonkey by David Bartlett. To enable, right-click in a multi-line text box, select "Languages", then "English / United Kingdom".
9,507 users
Latin Dictionary
Latin dictionary
1,032 users
Greek spellchecking dictionary
Greek spellchecking dictionary Mozilla (Firefox- Thunderbird- Seamonkey)
17,877 users
Icelandic Dictionary
Icelandic Dictionary
993 users
enUS deDE bilingual dictionary
This is a bilingual dictionary for American English and German Standard German. It is meant for users who regularly write in German and English. With it, you will not need to manually switch between dictionaries for the two languages.
4,691 users
Reverso – Translation, dictionary
Translate and learn languages while browsing and watching movies, it’s free.
13,676 users
Mate Translate – translator, dictionary
Your all-in-one translator for web pages, highlighted text & Netflix subtitles. Translate and learn words in 103 languages.
34,970 users
Croatian Dictionary (Hrvatski Rječnik)
Croatian Dictionary (Hrvatski Rječnik) for Mozilla
6,363 users
English Popup Dictionary
An English Dictionary for Firefox Quantum which gives meaning of a word which is double-click selected on a webpage.
1,615 users
Српски речник - Serbian Dictionary
Српски правописни речник - Serbian (Cyrillic and Latin) spellcheck dictionary
3,759 users
New Zealand English Dictionary
New Zealand English Dictionary 1.0.1 for Firefox.
2,713 users