The muscles that gym junkies work on because they look good in the mirror, even if they don't make you stronger or more attractive. Biceps, triceps, pecs, abs.
A: Hey, chekc out chicken legs over there!
B: I know, he spends all his time working on his mirror muscles and drinking protein shakes.
A: Someone should really tell him that he looks ridiculous.
by Robertito March 21, 2012
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