train station vs railway station

train station and railway station both are nouns.

Word	Noun	Adjective	Verb	Adverb
train station	Yes	No	No	No
railway station	Yes	No	No	No

As nouns, train station and railway station are synonyms defined as:

train station and railway station: a terminal/node where trains load or unload passengers or goods

Other synonyms of train station include railroad station, railroad terminal, train depot.

train station (noun)	railway station (noun)
a terminal/node where trains load or unload passengers or goods	a terminal/node where trains load or unload passengers or goods