N e x u s

Non refert quam multos [libros], sed quam bonos habeas.
Seneca, Epistulae, XLV, 1.

http://www.lexica.linguax.com/forc.php The famous “Lexicon totius Latinitatis” by Egidio Forcellini (very easy to search).

http://www.documentacatholicaomnia.eu/25_90_1688-1768-_Forcellini_Aeg.html The same, in pdf form.

http://www.perseus.tufts.edu/hopper/resolveform?&lookup=&lang=la A Latin-English dictionary (Lewis-Short).

http://www.prima-elementa.fr/Dico.htm A Latin-French dictionary.

http://gerardgreco.free.fr/IMG/pdf/Gaffiot_2016_-_komarov.pdf A Latin-French dictionary (the new Gaffiot).

http://www.zeno.org/Zeno/0/Suche?q=&k=Georges-1913 A Latin-German dictionary (Georges).

https://archive.org/details/dizionariolatino00calouoft A Latin-Italian dictionary (Georges-Calonghi).

https://www.grand-dictionnaire-latin.com/ An online Latin dictionary (in French).

http://www.lexica.linguax.com/wagner.php A Latin dictionary, with synonyms, antonyms and a phraseology (Wagner).

https://archive.org/details/bub_gb_lakQ_wn5mwwC “Latin synonyms”, by Schultz (in Italian).

http://gallica.bnf.fr/ark:/12148/bpt6k61498463.swf.f4.langFR Another treatise on Latin synonyms (in French).

http://www.lexica.linguax.com Many links to Latin and Greek dictionaries.

http://www.lexilogos.com/latin_langue_dictionnaires.htm A lot of links to Latin dictionaries and other reference works.

http://archives.nd.edu/latgramm.htm “Latin dictionary and grammar aid.”

https://archive.org/stream/latinphrasebookt00meis#page/8/mode/2up A Latin phrasebook.

https://archive.org/details/MedievalLatinLexicon A dictionary of medieval Latin (Niermeyer, in French and English).

http://ducange.enc.sorbonne.fr/ The “Glossarium mediae et infimae Latinitatis”, by Charles du Fresne lord du Cange (in Latin).

http://www.neulatein.de/ A Latin-German dictionary: from Petrarch to the year 1700.

https://archive.org/stream/dizionarioitalia00calo#page/n5/mode/2up An Italian-Latin dictionary (Calonghi-Rivoire).

http://www.vatican.va/roman_curia/institutions_connected/latinitas/documents/rc_latinitas_20040601_lexicon_it.html An Italian-English dictionary of neologisms.

http://juan23.edu.ar/latin/ A Spanish-Latin dictionary of modern words.

http://www.josephsusanka.com/latin An English-Latin dictionary: to translate modern words into Latin.

http://archimedes.mpiwg-berlin.mpg.de/cgi-bin/archim/dict/hw?step=list&id=d004&max=50 The best Greek dictionary (Liddel-Scott).