← BackshareGuessunvented/ʌnˈvɛntɪd/adjectiveNot provided with a vent or opening for air or gas to escape.The unvented gas heater can be dangerous in a small room.The attic was unvented, causing moisture to build up over time.They installed an unvented fireplace that recirculates the air.SynonymssealedAntonymsvented