a noun for that sketchy guy at the party that nobody knows. usually 10-20 years older than everybody else there. Generally wears a trucker hat, hiking boots and a trench coat - even when it is the middle of the summer. Generally hangs out in the coat closet and steals a jacket or two at every party they attend. Nobody likes a biolsi.
Guy 1:Who the heck is that in the closet?
Guy 2:No worries, it's just a biolsi
Guy 1:What's it gonna do?
Guy 2:It's gonna steal your mom's rain coats
by rawdawggg May 01, 2011

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