M.O.S. 

Member of Opposite Sex.

I have engaged in foreplay with an M.O.S.

M.O.S. by Dash_Morlock July 21, 2010

M.O.S. 

Make Out Session. Normally takes place while intoxicated. Not to be confused with F.O.S which is a fire up session, or a F.I.S. (when you fire inside a girls guts, deposit your kids in the women's belly).

We M.O.S.'ed (pronounced mossed) for a long time.

M.O.S. by Brian Dbag Peters April 22, 2006

M.O.S. 

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!

M.O.S. by michael foolsley February 12, 2010

M.O.S. 

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.

M.O.S. by Safety190 September 1, 2010

M.O.S

Multiple Orgasm Syndrome -

An ever-looming threat that hangs around the corner for all of us. Happens whenever we see someone wearing a comically sexy outfit such as jorts or socks and sandals. Results in a lot of cumming and moaning and is uncontrollable.

"Bro you shouldn't wear those jorts you don't wanna give the ladies M.O.S."

M.O.S by ahahano October 12, 2019

M' & O's

Multiple Orgasms

Used like one would use xoxo (hugs and kisses) at the close of message..

Promising to give pleasure

Miss you babe...
m's & o's ;)
M' & O's

M' & O's by Tattooed13 December 29, 2016

M.O.S

millennial outrage syndrome (MOS): the constant need to find outrage in everything all the time.

Jeff has a raging case of M.O.S.

M.O.S by E Towne August 31, 2019