abbrev. for Chill Out Slut; used when firing out the word "slut" is inappropriate, i.e. in a grocery store, courthouse, workplace, in front of children, etc. Encouragement for someone to relax, settle down, get out of your way, shut the hell up, etc.
Crazy bitch: "Did you hear about this and that and the other thing and this other thing and that person and what she did and he said and about what color underwear I'm wearing and what kind of weave do you have and where did you get that purse and did I tell you...."
Me: "OMG! COS! Seriously!
Me: "OMG! COS! Seriously!
by COSsayer March 30, 2011
"John really believes in COS, dude."
"Yeah he was wearing sweatpants and a sweatshirt to the club last night."
"Yeah he was wearing sweatpants and a sweatshirt to the club last night."
by COS pro June 07, 2013
by Raqueli88 September 04, 2006
John: Eric was really hammered last night after the fundraiser. He must have had 20 beers.
Jason: Yeah, he’s the COS.
Jason: Yeah, he’s the COS.
by Bamalama Johnson April 07, 2008
by Cake.Slaughter November 15, 2022
by Frank Rider August 23, 2009