However, there are some nuances:
* Earlier dictionaries existed in manuscript form. The *Lexicon* was the first printed dictionary in the modern sense, but there were earlier dictionaries in manuscript form. For example, a dictionary of Latin words was compiled in the 1st century AD by Flavius Josephus.
* The definition of "dictionary" can be debated. Some people might consider earlier works, like bilingual glossaries, to be dictionaries.
Therefore, the answer to the question depends on how you define "dictionary." However, the *Lexicon* by Ambrosius Calepinus is widely considered to be the first printed dictionary in the modern sense.