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1. Complement
To go well with; to complete.
That lamp complements your desk perfectly.
by Diggity Monkeez Mar 3, 2005 add a video
2. complement
In Math, the complement is, simply put, that which is outside of the defined region. However, this is often used as an insult in geek circles.

Geek 1:Your momma's so fat, that she's the complement of your house.

Geek 2: Yeah, well at least my penis isn't always the complement of a vagina.

Geek 1: *shoots self, thus becoming the complement of existing*
3. complement
something you give to someone you like
something you add to food to improve its taste
She accepted the complement with good grace
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