To pimp.
To forcibly perform anal sex upon an unwilling partner.
Ricky punked his new cell-mates.
To prank.
I got expelled when I punked the principal.
(especially with "out") To give up or concede; to act like a wimp.
Jimmy was going to help me with the prank, but he punked (out) at the last minute.
(often with "out" or "up") To adapt or embellish in the style of the punk movement.