cable railway vs railway line

cable railway and railway line both are nouns.

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

As nouns, railway line is a hypernym of cable railway; that is, railway line is a word with a broader meaning than cable railway:

cable railway: a railway up the side of a mountain pulled by a moving cable and having counterbalancing ascending and descending cars
railway line: line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight

Other hypernyms of cable railway include railroad, railroad line, railway, railway system.

cable railway (noun)	railway line (noun)
a railway up the side of a mountain pulled by a moving cable and having counterbalancing ascending and descending cars	the road consisting of railroad track and roadbed
	line that is the commercial organization responsible for operating a system of transportation for trains that pull passengers or freight