What is Seal The Deal?
1.
To reach the point where it is a virtual certainty that a given thing will happen. Often used in a sexual sense.
The first 5 drinks that Ron bought the girl at the bar definitely improved his chances to
beat it up , but the roofies he slipped in the 6th drink really sealed the deal.
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2.
When a straight guy does something that convinces everyone who's watching him do it that he's officially gay (or gives everyone the right to call him gay from them on).
Dude, John... You're already wearing a dress from the last bet. Kissing Adam right now for another 20 bucks would just seal the deal.
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