Part of the Bro-code.

Stands for; If a Bitch Gives you Shit Fuck them Off.

More emphasis when screamed really loud at your boys that your trying to protect from those evil bitches.
Boy 1: How is your girlfriend going?
Boy 2: Man, she's being so hard to deal with...
Boy 1: IABGUSFTO!
by Kingillst#1 August 14, 2012
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