motorbus vs passenger vehicle

motorbus and passenger vehicle both are nouns.

Word	Noun	Adjective	Verb	Adverb
motorbus	Yes	No	No	No
passenger vehicle	Yes	No	No	No

As nouns, motorbus and passenger vehicle are synonyms defined as:

motorbus and passenger vehicle: a vehicle carrying many passengers; used for public transport

Other synonyms of motorbus include autobus, bus, charabanc, coach, double-decker, jitney, motorcoach, omnibus.

motorbus (noun)	passenger vehicle (noun)
a vehicle carrying many passengers; used for public transport	a vehicle carrying many passengers; used for public transport