passenger car vs coach

passenger car and coach both are nouns.

Word	Noun	Adjective	Verb	Adverb
passenger car	Yes	No	No	No
coach	Yes	No	Yes	No

As nouns, passenger car and coach are synonyms defined as:

Other synonyms of passenger car include carriage.

passenger car (noun)	coach (noun)
a railcar where passengers ride	a carriage pulled by four horses with one driver
	a railcar where passengers ride
	a vehicle carrying many passengers; used for public transport
	a person who gives private instruction (as in singing, acting, etc.)
	(sports) someone in charge of training an athlete or a team

passenger car (verb)	coach (verb)
	teach and supervise (someone); act as a trainer or coach (to), as in sports
	drive or operate a coach or carriage