ethyl group vs alkyl

ethyl group and alkyl both are nouns.

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

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

ethyl group: the univalent hydrocarbon radical C2H5 derived from ethane by the removal of one hydrogen atom
alkyl: any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons

Other hypernyms of ethyl group include alkyl group, alkyl radical.

ethyl group (noun)	alkyl (noun)
the univalent hydrocarbon radical C2H5 derived from ethane by the removal of one hydrogen atom	any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons