Def. 1: Short for Gotta Boomerang, meaning you got to leave/go but will be back.

Def. 2: To say goodbye with intention of returning to one of the aspects of the environment you left, usually returning to see a certain person again.
Dude 1: "Aw man, I'm lateGotta Boom!"

Dude 2: "Aight, see you later then."

Example 2-

Girl 1: "My BF wants me to come over, Gotta Boom!"

Girl 2: "Oooh, Have Fun!"
by Cor-Pie November 23, 2013
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