noun. Mark Peters is enjoying this definition. Oh yeah.
Real citation: "Talking on Twitter without my usual third-person-osity is HARD"
(Aug. 22, 2009, Mike Stanton, Twitter, http://twitter.com/DoGudSnd/statuses/3473432579)
Made-up citation: "If you can't handle the third-person-osity, then maybe you're not ready to date Mark Peters and his tight abs, smooth testicles, pert buttocks, and watermelon-sized man-hooters."