railroader vs railwayman

railroader and railwayman both are nouns.

Word	Noun	Adjective	Verb	Adverb
railroader	Yes	No	No	No
railwayman	Yes	No	No	No

As nouns, railroader and railwayman are synonyms defined as:

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

railroader (noun)	railwayman (noun)
an employee of a railroad	an employee of a railroad