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An obnoxious frat boy who hangs out with the boys way too much. Combination of "frat" and "fanatic".
Frat Guy 1: Dude, Johnson is a total fratnatic. He needs to

meet some ladies.

Frat Guy 2: Agreed. He's been having a little too much bro

time.
by Kamikaze Kool-Aid Man September 30, 2010
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Apr 28 Word of the Day
Literally everyone, ever. Including the writer of this definition.
by masokitsune January 17, 2019
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