Whitaker's Words Easy to download, easy to use. This program can save you an immense amount of time if you download and install it on your computer.
Perseus Project You can access the Lewis and Short dictionary from here, which is a very good Latin lexicon.
LatinLexicon This online lexicon is well-organized and easy to use. It looks like it's being maintained regularly, too.
Google Translate Yes, Google Translate works for Latin, though be careful with what you get here.
Declension Dictionary In Italian. Enter words in the top bar and click "Trova" to search. Nouns should be in nominative singular, verbs in first person present ("amo," "dico," etc.), and adjectives in masculine singular nominative. If you don't know the correct form, enter a word and check "Cerca nelle forme flesse," which will search inflected forms.
Lewis and Short (from Perseus) A quick link to the lexicon. It's easiest to use the boxes at the top of the screen to navigate.
Copious and Critical Latin Dictionary It's both copious and critical.
Latin Dictionary for Schools Those school kids must have been experts in the classics.
Latin-English Dictionary For junior students. Not sure how to tell if you are one though.
Copious and Critical Dictionary #2 Also both copious and critical.
English-Latin Dictionary For the use of schools and colleges.
Copious Latin Lexicon The only downside is that it's not critical.
Latin Phrase-Book Translated from the German.
Dictionary of Latin Phrases A methodological digest.
Latin-Italian Dictionary Io sono di Roma.
Latin Etymological Dictionary Very old.
Handbook of Latin Synonyms Based on a German work.
Dictionary of Latin Synonyms For schools and private students.
Dictionary of Latin Quotations For parties!
Another Dictionary of Latin Quotations Classical and medieval quotes.
Latin Word List Easy to navigate.
Latin/English and English/Latin Verbs must be input in the first-person singular.
Medieval Latin in Saxon Words for specific works.
Latin > English Fairly old; the site itself says that better lexical tools are now available.
English > Latin Easy to navigate and a good basic resource.
Latin Quotes and Phrases To impress and annoy. Mostly the latter.
Computer Phrases in Latin You know, just in case.
Glossary of Latin Terms, Names, and Phrases Many commonly-used phrases.
Glossa Online Dictionary A fast, useful Latin dictionary, based off of Lewis and Short. The best part: there's a downloadable (alpha) version!
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