coach vs dining car

coach and dining car both are nouns.

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

As nouns, dining car is a hyponym of coach; that is, dining car is a word with a more specific, narrower meaning than coach:

coach (noun)	dining car (noun)
a carriage pulled by four horses with one driver	a passenger car where food is served in transit
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)	dining car (verb)
teach and supervise (someone); act as a trainer or coach (to), as in sports
drive or operate a coach or carriage