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1.
A Grimmo is an adjective, used to describe a person/s. Usually it is used to refer to someone who performs the act of 'grimacing' more often than not. A true Grimmo is a person who negatively affects his/her surroundings- or grims them out. It has recently been adapted to be used as part of other words, such as: Grimbosauras Rex, The Grimminator, and Grimbo Baggins.
"That guy is such a Grimmo!"
"Will, you grimmed out the ash tray! Your such a Grimmo!"
"You see that guy over there, he is definitely a Grimmo, he just looks so grim!"
by The Military Genius January 19, 2012