An acronym standing for "Make Out City" usually the place you go with a girl/guy when you think he/he is really hot and you want to "swap some spit" or "french it up". Mostly pertaining to young, hormonal couples or "make-out buddies" for those of you who are lucky. Also known as first base or just plain, classic making out.
Gerardo: So yeah, my woman came came over yesterday.
Other Dude: Did you guys go to M.O.C?
Gerardo: You know it brraaaahhhhh!!!