Entry 1 sense Webster, 1913 Butane /(bū"tān)/ · Bu·tane · IPA /ˈbjuːteɪn/ 01 n. An inflammable gaseous saturated hydrocarbon, C4H10, of the marsh gas, or paraffin, series. 1. An inflammable gaseous saturated hydrocarbon, C4H10, of the marsh gas, or paraffin, series.(Chem.)