1. give vent to one's anger. 2. An opening permitting the escape of fumes, a liquid, a gas, or steam. 3. The small hole at the breech of a gun through which the charge is ignited. 4. The excretory opening of the digestive tract in animals such as birds, reptiles, amphibians, and fish. 5. The opening of a volcano in the earth's crust. 6. An opening on the ocean floor that emits hot water and dissolved minerals. 7. To give often forceful expression or utterance to. 8. To release or discharge (steam, for example) through an opening. 9. To provide with a vent.