methyl radical vs alkyl radical

methyl radical and alkyl radical both are nouns.

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

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

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

Other hypernyms of methyl radical include alkyl, alkyl group.

methyl radical (noun)	alkyl radical (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