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8.
Member of Opposite Sex.
I have engaged in foreplay with an M.O.S.
by Dash_Morlock July 20, 2010
 
9.
man of steel (or 'men')

the 'macho man' who has huge pain tolerance, physically OR emotionally!; ESPECIALLY WHEN DRUNK!!
jack was a true M.O.S.!! he took on some killer bikers and got seriously thrashed, but bounced back like a turd that wouldn't flush!

he didn't know what he was in for challenging those M.O.S.

the special op M.O.S. kept on shooting after losing part of a leg, until he keeled over from blood loss!
by michael foolsley February 12, 2010
 
10.
M.O.S.=Member of Society:

someone who works, doesn't live with his parents and has a girlfriend. As well as this he does things regualr people do like go to the gym, wear a suit to work and buys beers in rounds at the pub.
that boy wears a suit to work, he's an M.O.S.

I saw him jogging with his girlfriend, what an M.O.S.

mate he's busy being an M.O.S. he ain't gonna come out.
by Safety190 August 28, 2010
 
11.
MOS
Stands for Ministry of Sound, a highly successful nightclub in London where they play electronica and stuff.
person a: did you get that mos annual cd?
person b: why dont you go to my amazon wishlist and buy it for me
person a: ok!
by Steven Bao August 02, 2006
 
12.
MOS
Mom over shoulder, often said in AIM to keep the reciever of the message from saying something particuarly "nasty" or "questionable"
DarkBob101:MOS
UT4k2:What the hell does that mean?
Darkbob101:Too late...
by Connor September 30, 2004
 
13.
MOS
make out slut.
Naw, she's an MOS.
by makeoutslut June 01, 2010
 
14.
MOS
Man on the side; meaning a man you have secretly in addition to your current relationship. Sometimes developes into a boyfriend/girlfriend relationship.
I'm going to LA to meet my MOS for a great weekend away from the hubby.
by Cali 521 July 22, 2008