Someone who snitches to the cops about illegal activity. Usually mob related.
That guy's a fucking Rat Head, he told the cops about Johnny selling weed.

He's a rat, the whole family are a bunch of Rat Heads.
by CakalakaJoe October 10, 2006
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To be really fucking shitfaced

See Tineyed
Junt - "Man I was fuckin' Rat Headed last night"

Ash - "Yeah Boy"
by too_fast June 21, 2011
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