a mad, fat, musical man who smells terrible, sweats like a pig, calls everyone son (including girls and people his own age), never remembers names including his own, has the word mackay somewhere in his name and is mentally retarded.
Girl: sits down in a classroom
Mad MacKay: ''You can't sit there, son!!!'
Girl: thinks to herself 'what a mad mackay!!!'
by scottdastalker January 14, 2011
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