motorcoach vs autobus

motorcoach and autobus both are nouns.

Word	Noun	Adjective	Verb	Adverb
motorcoach	Yes	No	No	No
autobus	Yes	No	No	No

As nouns, motorcoach and autobus are synonyms defined as:

motorcoach and autobus: a vehicle carrying many passengers; used for public transport

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

motorcoach (noun)	autobus (noun)
a vehicle carrying many passengers; used for public transport	a vehicle carrying many passengers; used for public transport