Home › Words › H › heliairheliair/ˈhiː.liˌɛə/heliair means A mixture of helium, nitrogen and oxygen, used as a breathing gas instead of normal air.heliair is pronounced /ˈhiː.liˌɛə/.EtymologyBlend of heli(um) + air.nounA mixture of helium, nitrogen and oxygen, used as a breathing gas instead of normal air.Definitions & examples from Wiktionary (CC BY-SA 3.0).