dormitory vs dormitory room

dormitory and dormitory room both are nouns.

Word	Noun	Adjective	Verb	Adverb
dormitory	Yes	No	No	No
dormitory room	Yes	No	No	No

As nouns, dormitory and dormitory room are synonyms defined as:

dormitory and dormitory room: a large sleeping room containing several beds

Other synonyms of dormitory include dorm room.

dormitory (noun)	dormitory room (noun)
a college or university building containing living quarters for students	a large sleeping room containing several beds
a large sleeping room containing several beds