diamondback vs rattlesnake

diamondback and rattlesnake both are nouns.

Word	Noun	Adjective	Verb	Adverb
diamondback	Yes	No	No	No
rattlesnake	Yes	No	No	No

As nouns, rattlesnake is a hypernym of diamondback; that is, rattlesnake is a word with a broader meaning than diamondback:

diamondback: large deadly rattlesnake with diamond-shaped markings
rattlesnake: pit viper with horny segments at the end of the tail that rattle when shaken

Other hypernyms of diamondback include rattler.

diamondback (noun)	rattlesnake (noun)
large deadly rattlesnake with diamond-shaped markings	pit viper with horny segments at the end of the tail that rattle when shaken