s/o 

significant other

"yea john is my s/o, we've been together for 10 years."

s/o by fediiphobicc January 24, 2022

S.O. 

Abbreviation for "Significant Other". The gender-neutral way to refer to someone's boy/girlfriend.

I'm having a party at my place. Bring your S.O.!

S.O. by The Grammar Nazi November 10, 2001

S.O. 

Means "significant other".

Hey, stop macking your S.O. and go home.

S.O. by unicore November 19, 2006

S.O. 

An amazing gaming clan based in Maine.

man I hate playing those S.O. guys they really trashed us in clan wars!

wow can you believe that %*#**in S.O. clan beat us like that?

S.O. by SO_nutcase911 January 7, 2014

S.O 

An acronym for Sexual Orientation.

"Dude, this Natasha girl is hot!"

"Right? RIGHT?"

"By the way, what's her S.O?"

"I hate to break it to you, man, but... I think she's gay."

"Gooooddddaammit! Actually, wait... that's pretty hot."

S.O by Danielakojas February 18, 2019

s.o 

sleep over

hey wanna s.o tonight?

s.o by polandspringthis May 8, 2010

S.O. 

An acronym for the derogatory term, saucey orifice, used instead of "significant other" to designate a woman that's kept around for physical pleasure. Can be used cladestinely in front of said S.O. when speaking to a friend who is "in the know". Said S.O. is lulled into a false sense of security thinking that they are your "significant other". (Only heterosexual use allowed as any other orifice is only saucey after the fact.)

Bob: Albert, just who is this engaing creature?

Albert: Oh, this is my S.O., Fillmein. Fillmein this is Albert. (Wink....wink)

S.O. by BigBlackBlick February 3, 2010