(1):

(n.) A portion; share; allowance.

(2):

(v. t.) To divide into shares; as, to whack the spoils of a robbery; - often with up.

(3):

(n.) A smart resounding blow.

(4):

(v. t.) To strike; to beat; to give a heavy or resounding blow to; to thrash; to make with whacks.

(5):

(v. i.) To strike anything with a smart blow.