train fare vs fare

train fare and fare both are nouns.

Word	Noun	Adjective	Verb	Adverb
train fare	Yes	No	No	No
fare	Yes	No	Yes	No

As nouns, fare is a hypernym of train fare; that is, fare is a word with a broader meaning than train fare:

Other hypernyms of train fare include transportation.

train fare (noun)	fare (noun)
the fare charged for traveling by train	an agenda of things to do
	the food and drink that are regularly served or consumed
	a paying (taxi) passenger
	the sum charged for riding in a public conveyance

train fare (verb)	fare (verb)
	eat well
	proceed or get along