bitch-slap → χαστούκι, καλό χαστούκι, γερό χαστούκι
The term has different connotations for different speakers; it is often used to refer to an especially strong or completely unexpected slap, but some speakers consider bitch slap to refer only to a weak slap (expressing mild contempt, as though the person being slapped is too weak to be given a strong slap). This would distinguish it from the stronger pimp slap.
Due to the inclusion of the word bitch, this term is often considered misogynistic.
https://en.wiktionary.org/wiki/bitch_slap#English