- The ball joint of the humerus in a moose's skeleton.
- (slang) The noticeable shape of a man's penis when he is wearing tight clothes.
2005, Benjamin Tripp, Square in the Nuts, ISBN 1411628225, page 92:
- […] the VIP of the GOP, George W. Bush in full military flight suit, with his ejector harness giving him the worst moose knuckle in presidential history.
- (slang) The shape that is noticeable when tight-fitting clothing wedges between a woman's labia.
2008, Jess Lourey, August Moon, ISBN 0738713252, page 8:
- I was grateful for the distraction, as I had been trying to look anywhere but at the giant moose knuckle spray-painted between her thighs […]
2009, Chuck Palahniuk, Snuff, ISBN 0385664699, page 68:
- At her crotch, the black spandex stretches to cover a small bulge. Bigger than camel toe. Swelling bigger than moose knuckle. Way bigger than a clit […]