rattler vs railroad train

rattler and railroad train both are nouns.

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

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

rattler: a railroad train consisting of freight cars
railroad train: public transport provided by a line of railway cars coupled together and drawn by a locomotive

Other hypernyms of rattler include train.

rattler (noun)	railroad train (noun)
pit viper with horny segments at the end of the tail that rattle when shaken	public transport provided by a line of railway cars coupled together and drawn by a locomotive
a railroad train consisting of freight cars