railway man vs railroad man

railway man and railroad man both are nouns.

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

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

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

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