railway man vs trainman

railway man and trainman both are nouns.

Word	Noun	Adjective	Verb	Adverb
railway man	Yes	No	No	No
trainman	Yes	No	No	No

As nouns, railway man and trainman are synonyms defined as:

Other synonyms of railway man include railroad man, railroader, railwayman.

railway man (noun)	trainman (noun)
an employee of a railroad	an employee of a railroad