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1.
or "MJS" for short.
Condition in which a female has an abnormally square/manly jaw.
Emily Deschanel (from the TV series, "Bones")

Jim: goddamn homie, she's fine!
Tim: yeah, but she's got a serious case of Man Jaw Syndrome
Jim: shitbiscuits, you're right
Tim: you bet you're black ass I'm right
by puertorican120 June 27, 2011