streamliner vs railroad train

streamliner and railroad train both are nouns.

Word	Noun	Adjective	Verb	Adverb
streamliner	Yes	No	No	No
railroad train	Yes	No	No	No

As nouns, railroad train is a hypernym of streamliner; that is, railroad train is a word with a broader meaning than streamliner:

streamliner: a streamlined train
railroad train: public transport provided by a line of railway cars coupled together and drawn by a locomotive

Other hypernyms of streamliner include train.

streamliner (noun)	railroad train (noun)
a streamlined train	public transport provided by a line of railway cars coupled together and drawn by a locomotive