Other forms: repertories
A repertory is a collection of pieces that are ready to be performed, like a theater's repertory of plays or a singer's repertory of songs.
The word repertory is very similar to the related repertoire, and they share the Late Latin root repertorium, "inventory or list." The French repertoire is generally more common, meaning "full range of what you can do." Repertory is more likely to specifically mean a theater or company of actors with a regularly performed repertoire of plays.