Definitions (Plato)

The Definitions (Greek: Ὅροι Horoi; Latin: Definitiones) is a dictionary of 184 philosophical terms sometimes included in the corpus of Plato's works. Plato is generally not regarded as the editor of all of Definitions. Some ancient scholars attributed Definitions to Speusippus.

In modern scholarship, Definitions is thought to have little philosophical value. Given the sophistication of Plato's and Aristotle's efforts in the area of definition, this collection seems to be an elementary text produced by second-rate philosophical study. Its early date, however, does give it some importance as a source for the history of ancient Platonism.