The act of smoking marijuana while doing laundry, followed by placing a batch of freshly dried/warm shirts upon the face resulting in a prolonged sensation of bliss.
Friend: What are you up to this afternoon?
Other friend: Shirting my ass off until all my laundry is done.
When a frat surrounds a celeb at a bar and encourages him/her to go completely topless. The topless celeb is rewarded with a shirt representing the letters of the fraternity.