A fat man who's diet consists of anything starting with 'Mc'. Known to populate and thrive in a fast-food environment, they will readily chow down anything fat-coated in sight, even if it isn't theirs.
'Dean P is such a fatty mac. '

Person 1: 'Holy fuck, did you see that?'
Person 2: 'I can't believe it!! He just ate all our food!'
Person 1: 'Man, what a fatty mac.'
Person 2: 'Yeah, I bet he spends his entire life eating and shoving his fat into people's faces to put them off.
Person 1: 'Nah, you've mixed him up with Rosie O'Donnell
by not a fatty mac August 29, 2009
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