Dictionaries et similia
Non refert quam multos [libros], sed quam bonos habeas.
Seneca, Epistulae, XLV, 1.
The “Thesaurus linguae latinae”, the largest Latin dictionary. Freely consultable online.
The famous “Lexicon totius Latinitatis” by Egidio Forcellini (very easy to search).
The same, in pdf form.
These four books are easily consultable online: Lewis-Short (the Latin-English dictionary), Smith-Hall (an English-Latin dictionary), Döderlein (a “handbook of Latin synonyms”) and the “Horae latinae” (“Studies in [Latin] synonyms and syntax”).
Some dictionaries: among them, Liddell-Scott, the best of all Greek dictionaries, and Lewis-Short, a Latin-English dictionary.
A Latin-English dictionary (Lewis-Short).
A Latin-French dictionary (the new Gaffiot).
A Latin-French dictionary.
A Latin-German dictionary (Georges).
A Latin-Italian dictionary (Georges-Calonghi).
An online Latin dictionary (in French).
A Latin dictionary, with synonyms, antonyms and a phraseology (Wagner).
“Latin synonyms”, by Schultz (in Italian).
Another treatise on Latin synonyms (in French).
Many links to Latin and Greek dictionaries.
A lot of links to Latin dictionaries and other reference works.
“Latin dictionary and grammar aid.”
“An historical dictionary and a linguistic encyclopaedia of Latin” (in French).
A Latin phrasebook.
A dictionary of medieval Latin (Niermeyer, in French and English).
The “Glossarium mediae et infimae Latinitatis”, by Charles du Fresne lord du Cange (in Latin).
A Latin-German dictionary: from Petrarch to the year 1700.
An Italian-Latin dictionary (Calonghi-Rivoire).
An Italian-English dictionary of neologisms.
A Spanish-Latin dictionary of modern words.
An English-Latin dictionary: to translate modern words into Latin.
The best Greek dictionary (Liddel-Scott).