Broadly used East Coast slang for people who exclusively hook up with ugly girls. A "Ross girl" or someone who is "Ross" is very unattractive and undesirable.

It has also been more broadly used to suggest anything other than a person that is bad in nature or ugly. The meaning has even been stretched to refer to getting severely drunk, wherein the person is in an ugly, drunken stupor.
"Damn, did you see that one Ross girl at the bar last night? She looked like chewbacca."

"Man, I had 8 tall cans of Bud and and 6 shots of tequila. I was so ross last night"
by RossinOut April 16, 2009
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