- whack - the sound made by a sharp swift blow
--1 is a kind of sound
- knock, belt, rap, whack, whang - the act of hitting vigorously; "he gave the table a whack"
--2 is a kind of blow
Derived form: verb whack1 - knock, belt, rap, whack, whang - the act of hitting vigorously; "he gave the table a whack"