Upvote:3
The French wikipedia page about the dictionary names two Latin authors who kind of wrote dictionaries, Varro and Verrius Flaccus. Then with the Christian era and the rise of the codex (book) and its religious use, you see a lot more, including the onomasticon (a kind of thesaurus) and a Latin-Greek dictionary in the 5th century.
But classification didn't go very far until printing spread literacy and made books both cheaper and more useful, which is why you start hearing about dictionaries in the renaissance period.