1. to get verbally assaulted as punishment or reprimand for one's foolishness or errors.
2. to have the outer rim of a bodily orifice, for example an anus, mangled or bludgeoned beyond repair, thus expanding and/or loosening said orifice and rendering it useless.
Mark: "I got reamed out by my boss today for storing feces in my desk."
2. Steve "What's with all the feces in your desk?"
Mark: "I got my asshole reamed out. I can no longer maintain my bowels."