noun

• (colloquial) Anything that is stunning.
• (colloquial, variant spelling "stunna") A woman of stunning beauty (often hyperbolically), a knockout.
• (professional wrestling) A professional wrestling maneuver in which an attacking wrestler applies a facelock to an opponent and falls to a seated position, forcing the opponent's jaw or neck to drop on the attacker's shoulder.
• (science fiction) A pistol firing a beam capable of stunning an enemy.
• A person or machine that stuns an animal before slaughter.