roof vs omnibus

roof and omnibus both are nouns.

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

roof (noun)	omnibus (noun)
a protective covering that covers or forms the top of a building	a vehicle carrying many passengers; used for public transport
protective covering on top of a motor vehicle	an anthology of articles on a related subject or an anthology of the works of a single author
an upper limit on what is allowed
the inner top surface of a covered area or hollow space

roof (adjective)	omnibus (adjective)
	providing for many things at once

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