coach vs passenger car

coach and passenger car both are nouns.

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

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

Other synonyms of coach include carriage.

coach (noun)	passenger car (noun)
a carriage pulled by four horses with one driver	a railcar where passengers ride
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

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