methyl group vs alkyl group

methyl group and alkyl group both are nouns.

Word	Noun	Adjective	Verb	Adverb
methyl group	Yes	No	No	No
alkyl group	Yes	No	No	No

As nouns, alkyl group is a hypernym of methyl group; that is, alkyl group is a word with a broader meaning than methyl group:

methyl group: the univalent radical CH3- derived from methane
alkyl group: any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons

Other hypernyms of methyl group include alkyl, alkyl radical.

methyl group (noun)	alkyl group (noun)
the univalent radical CH3- derived from methane	any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons