A person with whom you are not acquainted who sits directly next to you in a movie theater, play theater, or other public place along these lines. They then have the audacity to stretch their arm out onto what was once your armrest, creating any incredibly uncomfortable and unenjoyable movie-going experience.
"I was super pumped to watch the new Harry Potter movie, but this armrest ass pretty much ruined it for me.
by DaFerginator November 20, 2010
A term used to refer to someone who is so obese that their enormous ass is too large to fit in one seat, and must therefore occupy two, usually achieved by awkwardly straddling the armrest. This person is considered to be wearing an armrest thong. See also: Assassination
Obese man: Do you have anymore seats available for this flight?
Receptionist: We do... but you'll have to wear an armrest thong.
Guy: This armrest smells like ass!
Stewardess: Al Roker was sitting there the last trip.
Guy: In which seat?
Stewardess: Both.
Receptionist: We do... but you'll have to wear an armrest thong.
Guy: This armrest smells like ass!
Stewardess: Al Roker was sitting there the last trip.
Guy: In which seat?
Stewardess: Both.
by studio5insomniac October 22, 2010
when sharing armrests with a complete stranger, you should always use the front of the armrest on your left side and the back of the armrest on the right
by origami_XD September 04, 2016