A fork of Rural Dictionary
The bunching up of a zipper so it appears as if you have an erection protruding from your jacket.
Jim had a jacket boner and we laughed at how small it was.
A jacket boner is when your jacket zip pops up into the shape of a boner.
HAHAHAHAHA look that dood has a jacket boner
when you are wearing a zip-up jacket of any brand
and when zipped up it looks as if the zip line has multiple boners because of the numerous humps.
could also look like vaginas in extreme cases
Jacket made of erected foreskin.
Wow, Joey has one hard boner jacket.