It means change of subject. It is used more in the mediated communication genres such as texting, pming, iming, emailing, smsing, picture messaging, blogging, and ect...
Lisa Smith: Do these pants make my butt look fat?
John Smith: Hey babe, COS, we are going to be late if we don't leave right now!
by Ms. Busa November 17, 2009
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It means the passing of stool. Its origin is derived from Bill Cosby.
"Yo man I gotta drop a cos!"
by HFC Tru September 9, 2007
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Like Dawg, another attempt by black street thugs to address one another.
Yo cos, whereyou be hidin da crack?
by Moe Foe March 31, 2005
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Cup. Of. Sugar. A definition for a girl that is so hot that you would actually date her. You would go to her dorm/residence and make the excuse "i just needed to barrow a cup of sugar" because she is so hot.
Guy #1: Dude I went over to that cos's house today
Guy #2: really? she is so hot.. good for you
by rubydoo February 4, 2010
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The Zerg
Cant Organize Shit
Noob CareBear Alliance
Cos Zerged another city of 12 today

Cos is lead by an extremely flamboyant man named Herog.
by NB November 29, 2003
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A nick name for Conan O'Brien, given to him by Tom Hanks on the Tonight Show.
Conan hates being called Co Co
by Frank Rider August 23, 2009
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In 50-60s it was a slang word, meaning any woman who was a student on a predominantly male campus.

The term is almost not used except for in association with porn, it allows someone searching for porn to use a search term that would more likely produce a porn specific result.

For example compare the search results for “cute college girlvs “cute coed”
Young Horny Coed Engaging In Extremely Wild Fuckfest!
Coed Teen Absolutely Naked In Her Bed Waiting For Someone To Play!
Cute Horny Busty Blonde Coed Getting Slammed On The Massage Table!
by dildo777 April 6, 2021
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