Definitions by WoahMyNo

merfin 

someone who is tweaking on meth, or seems to be tweaking on meth, or just looks any sorts of sketchy

There is this guy sitting behind a bush at that park watching people; that dude's merfin.

Kellin Quinn advocates merfin awareness because no one likes a merf.

merfin by WoahMyNo September 7, 2012