trolley coach vs autobus

trolley coach and autobus both are nouns.

Word	Noun	Adjective	Verb	Adverb
trolley coach	Yes	No	No	No
autobus	Yes	No	No	No

As nouns, autobus is a hypernym of trolley coach; that is, autobus is a word with a broader meaning than trolley coach:

trolley coach: a passenger bus with an electric motor that draws power from overhead wires
autobus: a vehicle carrying many passengers; used for public transport

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

trolley coach (noun)	autobus (noun)
a passenger bus with an electric motor that draws power from overhead wires	a vehicle carrying many passengers; used for public transport