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 23, 2010
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