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1.
2 down ass gangsta girls
"DAMN NIGGA. Nathalie and Neena r fuckin COBA. dayum they cool as hell'
by LuCkY* January 23, 2007
 
2.
COBA or "c.o.b.a" is an acronym that stands for: Check Out By Association.

a "COBA" (pronounced: côh-bá) occurs when an attractive person is associated with an ugly or "unattractive" person, and said ugly guy or girl gets checked out, just because he/she is physically with a good-looking or even "hot" human being.

A COBA is a very tricky thing, if a COBA is initiated and the ugly person (who is usually checked out last) believes it was for their own looks, it may give the ugly one a false sense of confidence, that may lead to terrible choices of fashion; in clothing, hat selections and even worse, terribly unjustified arrogance. But, when COBA is noticed for what it is, the unattractive person can instantly return to his/her cyle of quiet self loathing.

Whether it be for selfish reasons i.e: making themselves look better in comparison (see also; duff) or the more noble paths: need of wingman/wingwoman, actually likes ugly person as a person: the better looking person always has a reason to be with their homely counterpart. Someone who has done a COBA can read the bond between the two, then analyze it from there.
David: "Bro, that cutie in the brown dress just totally checked you out!"

Juan: "No way man, she is SO not into fat dudes, plus, she friggin' eye-raped you first, that was a total COBA"

David: "a what?"

Juan:" a C.O.B.A!: check out by association, she checked you out cos' she wanted to, and me because she wanted to try to comprehend our friendship, and/or why you'd hang out with an ugly guy."
by John Kings jr July 11, 2009