reffers to someone who is completely and utterly unable to hang in social situation. sometimes segregating themselves entirely before events just to try and save face.

to bow out of an otherwise social activity (shots, thc smokage, beer can shotgunning..)

to agree to something until date (or time) of promise only to have change of heart and suddenly neglect responsabilities.
examples..
friend 1: where is Andrew at? i thought we were all taking shots
friend 2: pfft, that guy.. he's booning out

can also be used as an adverb

friend 1: i thought Moe was comming to the show tonight?
friend 2: what can i say? dude booned out
by big ole' handsome winnie July 28, 2012
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