(2) To be using drugs or found to be using through a test
(3) Shifty, greasy, unkempt, possession bad manners; having “redneck” qualities.
(4) A mullet
(2) Barry Bonds never showed up dirty on his tests because he took measures to ensure he showed clean.
(3) She's so dirty; he must be mad about her to wanna go out with someone s-o-o-o-o on the other side of the tracks.
(4) Dawg the Bounty Hunter has a helluva dirty.