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!

MOS by Steven Bao August 3, 2006

MOS 

make out slut.

Naw, she's an MOS.

MOS by makeoutslut June 1, 2010

mos 

a pussy bitch with a small dick

mos has a small dick

mos by yaknowprettymuchjuststuff October 15, 2018

mos 

a bastardization of mos def meaning "I concur" or "Affirmative"

"man, this food they're serving blows"
"mos."

-or-
"are you going to join the riots tonight?"
"mos."

mos by Mos Def January 21, 2004

MOS 

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*

MOS by International Lesbian Actor, George Clinton September 18, 2006

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.

MOS by Cali 521 August 19, 2008

Mos 

Mom over shoulder

I can’t talk right now mos

Mos by Marspott October 29, 2017