In a fraternity or sorority, when one or more memebers are trying to successfuly get a potential member to consider joining (or "Rush" them), when all of the sudden another member says something stupid and blows the deal.
Phil: hey man, this fraternity is perfect for you. Totally straight and cool.

Dustin: yea? I totally feel yo...

David (interupting): dude Ryan just grabbed my cock haha why did I join this fraternity... so gay...

Phil: God damnit, what a Rush Block...
by aewhat6969 February 4, 2010
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