Greek WordNet is a database of the Greek language from Mycenaean and Homeric epics. The GreekWordNet API exposes the data from the database in in JSON format. This includes detailed information about individual lemmas (canonical form, dictionary form, or citation form of a set of words) and synsets (synonymous words), translation, and sentiment analysis. Ancient Greek WordNet is a collaboration between Harvard's Center for Hellenic Studies, the University of Exeter, and the University of Pavia. Extensions into the Classical, Hellenistic, and Roman periods are in planning.