passenger vehicle vs motorbus

passenger vehicle and motorbus both are nouns.

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

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

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

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

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