A police informant; a "rat".
Hey, I thought I got away with that burglary but my crime-partner pulled a McGruff on me.
by Bobby Rose November 10, 2007
A guy that Hangs out at Old #3 in Roslyn, WA trying to get young guys to go to the bathroom with him.
You want to go McGruff in the bathroom
by Baller42o May 26, 2009