chav/gangsta speech for 'is this because i am...'
also used in amusement when talking to security guards.
Person 1: Yo, I'm gonna beat youz to shizzle.
Person 2: ..Iz it coz i iz blackkk mofo?

Security Guard: What are you doing in here?
Kid: Iz it coz i iz bla..bla.. (notices guard is black) ..wearing misfits?
Kid's friends: *break down in hysterics*
by CityofEvil July 14, 2007
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