A nudist practice involving wearing nothing but a shirt, usually a t-shirt that ends above the waste.
That smelly old hippie with the Burn It! t-shirt and no pants is shirtcocking in the wrong town. Get him!
verb: meaning to wear only a shirt and no pants or underwear, hence just a shirt and cock. However, can also be applied to girls. May have first been created at Burning Man.
I only saw his little pale butt as he was shirtcocking when he chased my cat Snickers out of the room.