Rest Wrinkle
n. The taper in a turd that occurs when one loses fecal focus during the act of defecation and the anus contracts slightly. usually caused by a distraction such as a knock on the door, a cough, etc. may also be caused by a defecation with such girth/mass that the defecater may need to take a rest.
ie: Half asleep, Roger opened the unlocked bathroom door causing Margaret to make a rest wrinkle.