The "sidefoul" or bad breath one emits from the side of the mouth when slightly opened at the point of exhaling. Mostly occurring when one is seated next to another person; ie. commuter train, public transit, carpool, movie theater, etc. Foul smells include but not limited to; milk, onion, olives, alcohol, cheese, morning breath etc.
I would have enjoyed my commute to work if I hadn't sat down next to this person committing a sidefoul.
by mr. *zee April 17, 2015