butane vs methane series

butane and methane series both are nouns.

Word	Noun	Adjective	Verb	Adverb
butane	Yes	No	No	No
methane series	Yes	No	No	No

As nouns, methane series is a hypernym of butane; that is, methane series is a word with a broader meaning than butane:

butane: occurs in natural gas; used in the manufacture of rubber and fuels
methane series: a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)

Other hypernyms of butane include fuel, gas, alkane, alkane series, paraffin, paraffin series.

butane (noun)	methane series (noun)
occurs in natural gas; used in the manufacture of rubber and fuels	a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)