Omnidict

Omnidict is a fast offline dictionary for the Linux desktop. Choose from more than six hundred free dictionaries in hundreds of languages, download the ones you need once, and look words up instantly, without an internet connection.

A dictionary for every language:

• English dictionary and thesaurus: English Wiktionary definitions, and English WordNet with synonyms, antonyms and related words
• Wiktionary for over three hundred languages: Spanish, French, German, Italian, Portuguese, Russian, Hindi, Arabic, Japanese, Chinese, Korean, Turkish and many more, each explained in English
• Historical languages too: Latin, Ancient Greek, Old English, Sanskrit and Old Norse
• Hundreds of bilingual FreeDict dictionaries, such as German-English, English-French and Spanish-Portuguese
• JMdict Japanese dictionary, CC-CEDICT Chinese dictionary and Kengdic Korean dictionary
• Filter the catalogue by language and provider, and see each dictionary's size and number of entries before you download

Look words up quickly:

• Word lookup as you type, results grouped by dictionary with the best match first
• Accents are optional, and an inflected form finds its entry: ran finds run
• "Did you mean" spelling suggestions for misspelled words, in every script
• Wildcards: ? for one letter, * for any run of letters
• Full text search finds words used inside definitions
• Links between entries, with Back and Forward as in a browser
• Quick lookup: select a word in any app and press a shortcut to see its meaning in a small window

Made for learning and everyday use:

• Favourites and recent lookups to build your vocabulary
• Reorder dictionaries, switch them off, update or remove them
• Light and dark themes that follow the desktop, and an adjustable text size
• Keyboard shortcuts for everything
• Private: no tracking, nothing is sent anywhere; the only network use is downloading dictionaries