An abbreviation for 'Muff Over Mates'
Used to describe when a
friend has disbanded or stitched up their own
group of friends, to spend
time with his or her partner instead.
Paul: Hey, where's Jerome got to? He's supposed to be meeting us in an hour…
Alan: I
don't think he's coming man, he called to say he was seeing
Kathy again
Paul: Man, that
guy is such a M.O.M!