The level of drunkenness attained (mostly by Individuals affiliated with a fraternity or sorority) by consuming large amounts of beer. It is somewhere between "drunk" and "blacked-the-fuck-out." Symptoms include: dancing, flirting with a member of the opposite sex, being very loud, and possessing an over inflated ego.
-Bro did you see mike last night? He was dancing with the with the chick with the huge mole on her chin.
-Dude he was so frat drunk last night

-I saw you making out with Michelle at the Halloween party
-Yeah man I was Frat Drunk last night

-You got the whole bar to sing Sweet Caroline last night
-Totally Frat Drunk
by dudeletsparty October 31, 2011
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