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2.
The sound a man makes when he is lifting to much weight in the gym.
I thought someone died in the gym the otherday, but it was just Mike having a gymgasm.
by Charles Crain January 18, 2009
 
1.
When an over zealous gym junkie is loving his workout so much he moans each time he lifts the weights.
-AT THE GYM-

Dean: " Hey Rhys, check out the dude in the corner haha"

*Dude in Corner*: "Urrrrrrgggghhhhhh"

Rhys: " Geez, sounds like hes having a Gymgasm, what a tool!"
by Dean Jacobs December 04, 2008