1. After the man in the black pajamas throws a grenade in the middle of your unit, the sacrificial act of covering the grenade with your body in order to shield your comrades from the blast.
2. To occupy (especially through sexual activity) a hot chick's ugly friend so that your friend can score with the hot one
Bill: I need you to sit on the grenade
Jim: No way, I wouldn't even give that girl a hot carl.
by Jake E. Pants July 15, 2002
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