flap·per 
(flăpər)
(flăpər)n.
1. A broad flexible part, such as a flipper.
2. A young woman of the 1920s who rebelled against conventional ideas of ladylike behavior and dress.
[Sense 2, British Slang, very young female prostitute, flapper, possibly from flapper, fledgling partridge or duck (from FLAP) or from dialectal flap, loose or flighty girl.]