Thesaurus linguae Latinae at Bavarian Academy of Sciences is the most authoritative dictionary of ancient Latin. It is the only lexicon to cover all surviving Latin texts from the earliest times down to AD 600. Scholars in Munich are working to compile the most comprehensive dictionary of Latin ever assembled. They’ve been at it for 125 years and now they’re up to R. With some luck, the Thesaurus Linguae Latinae will be finished around 2050.