roof vs sunroof

roof and sunroof both are nouns.

Word	Noun	Adjective	Verb	Adverb
roof	Yes	No	Yes	No
sunroof	Yes	No	No	No

As nouns, sunroof is a hyponym of roof; that is, sunroof is a word with a more specific, narrower meaning than roof:

roof (noun)	sunroof (noun)
a protective covering that covers or forms the top of a building	an automobile roof having a sliding or raisable panel
protective covering on top of a motor vehicle
an upper limit on what is allowed
the inner top surface of a covered area or hollow space

roof (verb)	sunroof (verb)
provide a building with a roof; cover a building with a roof