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1.
A term used when you or a friend know you're able to bang a chick. You have her "under the blanket"

Origiantes from the fact that when your watching a movie with a girl and you get under the same blanket with them your set to fuck. or at least make out. or get a blowjob. Or suck on some titties.
Man she was askin about you at work, you got her under the blanket.
by Herb311 October 24, 2004