palace car vs carriage

palace car and carriage both are nouns.

Word	Noun	Adjective	Verb	Adverb
palace car	Yes	No	No	No
carriage	Yes	No	No	No

As nouns, carriage is a hypernym of palace car; that is, carriage is a word with a broader meaning than palace car:

palace car: a passenger car for day travel; you pay extra fare for individual chairs
carriage: a railcar where passengers ride

Other hypernyms of palace car include coach, passenger car.

palace car (noun)	carriage (noun)
a passenger car for day travel; you pay extra fare for individual chairs	a vehicle with wheels drawn by one or more horses
	a railcar where passengers ride
	a machine part that carries something else
	a small vehicle with four wheels in which a baby or child is pushed around
	characteristic way of bearing one's body