When someone farts into a cushioned seat without lifting a cheek thereby injecting the air directly into the cushion which then causes the cushion to retain the fart odor long after the offending Farter has risen.

It is inconsiderate, and disgusting, and strictly prohibited by those who know what it is.
My brother injectile farted into my sofa, causing it to smell of a fart for days.
by AHGRP August 2, 2010
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