处女作 literally means 'maiden work' - same metaphor as English 'maiden voyage.' Used for any creator's first official release: novel, film, album, painting. Compare with 成名作, the work that made them famous, which may or may not be the debut.
memory
处女 = 'maiden/virgin' + 作 = 'work.' If 'maiden voyage' is a ship's first trip, 处女作 is an artist's first publication.
