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1.
Cleavan : A twisted drug freak. Someone who indulges in party prescriptions at every opportunity intent on reaching new levels of messyness with little or no regard for their wellbeing untill monday morning.

Also known to be prolific in and amongst the hardcore fraternity
Dude did you see the state of that guy the other night? He is such a cleavan.
by JoeMoore March 13, 2010