Okay, everybody else's definition of MOS is wrong. They are all stupid. Here is the real explanation: When a man loves a woman very very very much, they engage in an act called M. O. S. MOS stands for Mutual Oral Sex and is extremely pleasurable. Also see 69, Something that is awesome, the shit, the awesome, the best thing ever, etc.
Jennifer: Hey Austin, wanna MOS?
Austin: I like men.
Jennifer: Oh.
Jennifer: You don't know what MOS is, do you?
Austin: No. *Looks sad*
Austin: I like men.
Jennifer: Oh.
Jennifer: You don't know what MOS is, do you?
Austin: No. *Looks sad*
by International Lesbian Actor, George Clinton September 18, 2006
Get the MOSmug. Short for MOFO, which is short for Mother F'er... Used when somebody is being extremely MOFO-ic, and think they're a bad aaah from the skreets.
by Jena March 16, 2005
Get the MOmug. Short for 'moron'
by 1337 h4x0r November 20, 2003
Get the momug. by debbi domination November 5, 2008
Get the momug. When someone is taught something and deliberately does it there own way in spite. This often leads to disaster.
by Shydog October 16, 2008
Get the MOmug. Derived from the term "Homo" or "Homosexual" whereas the "Ho" beginning is used to describe the woman in a relationship with the gay man, subsequently named the "Mo"
by eugaet January 26, 2010
Get the Momug. by opaltime June 22, 2015
Get the Mo momug.