methylene group vs methylene radical

methylene group and methylene radical both are nouns.

Word	Noun	Adjective	Verb	Adverb
methylene group	Yes	No	No	No
methylene radical	Yes	No	No	No

As nouns, methylene group and methylene radical are synonyms defined as:

methylene group and methylene radical: the bivalent radical CH2 derived from methane

Other synonyms of methylene group include methylene.

methylene group (noun)	methylene radical (noun)
the bivalent radical CH2 derived from methane	the bivalent radical CH2 derived from methane