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1.
A judgment leveled against an otherwise perfectly proportioned, if not slightly trim, and pleasant looking woman. Generally uttered by a male who is way below her class.
Yeah sure she is really nice looking, but I wouldn't hit that. I mean look at those sharp knees!
by Dwight Frank September 30, 2005
 
2.
When a woman, specifically a celebrity or actress, is so thin (as to imply she is anorexic) that her knees appear sharp or pointy.
Calista Flockhart has sharp knees.
by the black rabbit April 29, 2005