When you take a poop and it kinda burns your butthole.

Got the covid-19 vaccine

1. the sensation that comes when one eats some spicy food (maybe some korean barbecue or a volcano box from taco bell) and takes a dump later on during the day, and feels as if his or her butt knew that the food was spicy.

2. a feeling burning around the anus after eating spicy foods and eliminating the resulting stool

note: the foods causing fire butt are not limited to spicy food.

The incredibly painful stinging sensation one receives on their anus, usually caused by indigestion and/or spicy foods.