Green’s Dictionary of Slang

wap v.

[SE wap, to throw violently, to pull down; note whop v.; Hencke suggests link to wap, a mongrel and thence to bitch n.1 (1)]

1. [mid-16C–early 19C] to have sex, usu. used of a woman.

2. [2010s] (UK Black) to shoot, to kill.

3. see whop v.