1. [mid-17C; 1910s+] (also flaps) a promiscuous woman; a prostitute.
2. [late 18C–1920s] any garment that has a pendant flap or flaps.
3. [late 19C] (UK Und.) strips of lead used on roofs.
4. [late 19C–1910s] the vagina.
5. [late 19C+] (also hearing flap, side-flap) an ear, usu. large.
6. [late 19C+] in pl., the labia majora.
7. [1950s+] (US) the mouth.
8. [1950s+] (Aus.) a cheque.
[early 18C] a whore.
[1970s+] in pornographic still or moving pictures, a close-up shot of the labia and open vagina.
[1990s+] vaginal secretions.
[1950s+] the ears.
[1940s] (US) the mouth.
SE in slang uses
see flap v.1
see blow with a French faggot-stick n.