What is the meaning of Whack?

The sound of a heavy strike.

The strike itself.

The stroke itself, regardless of its successful impact.

An attempt, a chance, a turn, a go, originally an attempt to beat someone or something.

A share, a portion, especially a full share or large portion.

A whack-up: a division of an amount into separate whacks, a divvying up.

A deal, an agreement.

PCP, phencyclidine .

The backslash, ⟨ \ ⟩.

Alternative spelling of wack (“annoyingly or disappointingly bad”)

To hit, slap or strike.

To assassinate, bump off.

To share or parcel out (often with up).

To beat convincingly; to thrash.

To surpass; to better.

To attempt something despite not knowing how to do it; to take on a task spontaneously and carelessly without planning.

To eat something hurriedly.

Alternative spelling of wack (“annoyingly or disappointingly bad”).

Source: wiktionary.org