ethyl group vs alkyl group

ethyl group and alkyl group both are nouns.

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

As nouns, alkyl group is a hypernym of ethyl group; that is, alkyl group 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 group: any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons

Other hypernyms of ethyl group include alkyl, alkyl radical.

ethyl group (noun)	alkyl group (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