hydroxyl group vs hydroxyl

hydroxyl group and hydroxyl both are nouns.

Word	Noun	Adjective	Verb	Adverb
hydroxyl group	Yes	No	No	No
hydroxyl	Yes	No	No	No

As nouns, hydroxyl group and hydroxyl are synonyms defined as:

hydroxyl group and hydroxyl: the monovalent group -OH in such compounds as bases and some acids and alcohols

Other synonyms of hydroxyl group include hydroxyl radical.

hydroxyl group (noun)	hydroxyl (noun)
the monovalent group -OH in such compounds as bases and some acids and alcohols	the monovalent group -OH in such compounds as bases and some acids and alcohols