OSO 

"Other significant other". A non-primary partner in a polyamorous relationship; a fuck buddy or friend with benefits.

"meeting new OSOs always makes me nervous."
"My SO found a new friend online; she's already talking about making him an OSO, which kind of squicks me."

OSO by guyjin March 23, 2007

Oso 

The delicate art of receiving a blow job while eating a sandwich ("sammich") that was lovingly prepared by the woman performing the blow job.

I thought getting a blumpkin was good, but getting an Oso is even better! Nom, nom, nom!

Oso by SacTownFamous January 2, 2012

OSO 

The Don , Top Dog , The king.

OSO said to do it. So I did it. It was OSO so I had no choice.

OSO by ?Idk! October 9, 2020

Oso 

Oso is a realy sweet and kind person who doesn't know how to deal with their emotions. There super hot and funny. They are rambuctous and hyper. Their hard working,caring, are pretty emotinal and have a lot going on in there life. They need friend to be there no matter what so they don't feel alone.

Person 1 "Hey why is Oso keeping to himself."
Person 2 "I don't know he hides his emotions."

Oso by Cuthotgirl October 15, 2018

oso 

a stuffed teddy bear on playhouse disney who is a bit special...
oso special in fact

little kids love him and adults get to rip him

oh no! i don't know how to tie my shoes! it's ok, special agent oso is here to help me! no... wait he can't do it either.

oso by jezzimommy May 20, 2010

oso 

mafiOSO, mafia, mob, vice lords, CVLN

I'M OSO FOOL, he's traight oso dog

oso by koop da kid May 4, 2006

oso 

Oso meaning ya name ring bells someone to be scared of he is a menace

oso is on the block we finna die

oso by chreme1789 November 13, 2020