An idiotic, slow and inept person who also uses way too much Oxycontin/Oxycodone. What is important to stress is that they would be a moron even without the Oxycontin/Oxycodone, but they're also a pillhead.
"Dang, where is Keith? He was supposed to meet us down at the lake an hour ago."
"Oh he's an Oxymoron... He went the wrong way... and smoked a month worth of 20's."