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A condition where broing it up so much eventually leads to a ridiculously huge gut.
Dude 1: Bro, Jim got huge since last year! What happened to him?

Dude 2: Jim's been broing it up hardcore bro. His pizza to workout ratio is way too big, a common cause of brobesity.
by Brahfizzle April 30, 2012
When you and your bros decide to become obese together.
Cashier: welcome to Mcdonalds. How may I help you.
Bro 1: We're going into brobesity, so we'd like 36 big macs, 20 large fries.
Bro 2: And 2 DIET Cokes.
by Fatty69696969 August 14, 2012