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1.
A close bro that will just bail out of anything at any given moment. Usually bailing on a bro night without the decency to hit up said bros and give them a heads up. Will some times bail to hang out with dime piece or other erroneous reasons.

can be closely related to a dippopotamus.
Example:

Bro 1: Yo where's Timmy at? Thought he was hitting up late night apps with us!

Bro 2: Ah haven't heard from him in a couple hours.

Bro: Dude he is such a bailosaurus.

Example 2:
Guy 1: Johnny, you still going out with us tonight?
Guy 2: Nah man i gotta walk my cat tonight.
Guy 1: God damn bailosaurus!
by not-a-bailosaurus September 12, 2013