short for mother fucking killa whale. similiar to BAMF, which means bad ass mother fucker. i made it up after listening to killa whale by andre nickatina all the time, becaue i am a MFKW. its basically a really bad ass, chill, cool, mother fucker. but adding killa whale makes it that much better.
a girl see's her friend and says : "what up BAMF?"

the friend replies : "dude, im a MFKW."
by hggufyufk February 26, 2009
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