An action of which you make the letter 'M' in sigh language with your fist then punching your target in the shoulder; usually this is done by the coolest of the coolest mammals (leaders, gold/silver/bronze badge holders, CraCra Mammal Crew).
*MaMMaL Punch*

'I so just *Mammal Punch*ed more people then you, I win the gold badge'
by Ashley Anne Lawson (Cubbie) September 12, 2003
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