alkyl vs alkyl radical

alkyl and alkyl radical both are nouns.

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

As nouns, alkyl and alkyl radical are synonyms defined as:

alkyl and alkyl radical: any of a series of univalent groups of the general formula CnH2n+1 derived from aliphatic hydrocarbons

Other synonyms of alkyl include alkyl group.

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