trackless trolley vs charabanc

trackless trolley and charabanc both are nouns.

Word	Noun	Adjective	Verb	Adverb
trackless trolley	Yes	No	No	No
charabanc	Yes	No	No	No

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

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

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

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