stinging sensation around the a-hole caused by spicy food eaten the night before, or on occasion a particularly violent and sharp turd that when released feels like your ass is being ripped
In U.K. a hot or extremely hot curry, such as vindaloo, tindaloo or phaal. Defenition refers to not the preliminary chilli peppery taste, but the secondary "afterburn" effects felt on the loo next morning.
I had ten pints and a vindaloolast night, what a ringstinger! I've been shitting through the eye of a needle!