A vent is an opening inside or outside of a building, a house, a car, a computer, a machine, etcetera. It allows for the passage of air and helps to regulate temperature.
I opened a vent to allow more heat into the room.
Can you open the vent, please?
The custodian for the building checked all the vents to make sure they were working properly.
If the vent is sealed, it won’t allow air to flow through.
vent
A vent is also an opening in a volcano. Gas, hot air, and lava come out through the vent.
You can see what looks like smoke coming from the vent.
Lava and ash erupted through the vent.
The volcano is venting gas.
The word "vent" can also be used as a verb. To vent is to express anger or show a raw emotional reponse:
The supervisor vented her anger towards the employees.
She later apologized for venting her anger. (This sentence uses "vent" as a gerund.)
Bob and his coworkers felt a need to vent after a long day at work, so they all went to the local tavern for a beer.