tiger rattlesnake vs rattler

tiger rattlesnake and rattler both are nouns.

Word	Noun	Adjective	Verb	Adverb
tiger rattlesnake	Yes	No	No	No
rattler	Yes	No	No	No

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

tiger rattlesnake: having irregularly cross-banded back; of arid foothills and canyons of southern Arizona and Mexico
rattler: pit viper with horny segments at the end of the tail that rattle when shaken

Other hypernyms of tiger rattlesnake include rattlesnake.

tiger rattlesnake (noun)	rattler (noun)
having irregularly cross-banded back; of arid foothills and canyons of southern Arizona and Mexico	pit viper with horny segments at the end of the tail that rattle when shaken
	a railroad train consisting of freight cars