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1.
T-Rexmode is a term similar to ottermode or bearmode given to a body type characterized by having a massive lower body and a tiny upper body like a Tyrannosaurus.

Someone becomes T-rexmode by following bad fitness advice and only doing squats and deadlifts instead of a full body workout.
Guy 1: Hey guys, how do I T-rexmode?
Guy 2: SQUATS AND OATS, BRAH
by Jadedboo July 19, 2010