A woman (usually a tennager) that uses air, tissues or paper to make the illusion that their breasts are larger than they really are. False advertisement.
"God Ashley is such a Coser!"
by Snarkle Janglebond May 11, 2006
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When someone is cosers, that means they are beyond comfortable.
"What are you up to Andrew?" "Well babe, I decided to get all cosers and await your return"
by Coolie Whistles August 24, 2019
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