railroad line vs railway

railroad line and railway both are nouns.

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

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

railroad line and railway: line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight

Other synonyms of railroad line include railroad, railway line, railway system.

railroad line (noun)	railway (noun)
line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight	line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight
	a line of track providing a runway for wheels