noun🔗ShareIn a pneumatic tire, the rubber liner that holds the air."The bicycle tire was flat because the innertube had a hole in it. "materialvehicleparttechnologyChat with AIVocabulary GamePractice Reading
noun🔗ShareThis rubber liner, used without the tire on water as a flotation aid."We used an innertube to float down the lazy river at the water park. "materialaidsportnauticalChat with AIVocabulary GamePractice Reading
