v. hwhacked, hwhack·ing, hwhacks

v.tr.
1. To repetatively stroke with a sharp slapping blow to provoke pleasure; pleasure-orientated activity; self-pleasuring
2. To masturbate strenously.
v.intr.
To bring pleasure to oneself. Hwack-ing off.

n.
1. A sharp, swift slap.
2. The sound made by a masturbator.
Phrasal Verb:
hwhack off: Vulgar Slang
To masturbate.

Idioms:
have/take a hwhack; Informal
out o
f hwhack; tired Informal
hwhacked out Slang
1. Exhausted.
2. Too much self-pleasuring.

synonyms: whack, smack, hit, beat