1 definition by Zack Wiggins

when going over a hill at high speeds and that euphoria feeling overcomes you; you let back your head and sigh going over a hill. Can also be used as an adjective: Hillgasmic
Billy: Dude did we just go over a hill?
Bob: Yea why?
Billy: Cause I just totally just had a Hillgasam
by Zack Wiggins February 11, 2009
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