One who was once skinny, frail, and weak then was taken by a muscle daddy (swole sensei) and buffed up.
"Why is Rich working out with us?"
"He's my newborn muscle baby."
by thePOGlife February 5, 2015
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A.A.C.D , basically weak
pumping serioids

no talent
weak
"omg look at baby muscles over there
he must have been taking steriods last night"
by thanamelessone December 8, 2009
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