cholla vs cactus

cholla and cactus both are nouns.

Word	Noun	Adjective	Verb	Adverb
cholla	Yes	No	No	No
cactus	Yes	No	No	No

As nouns, cactus is a hypernym of cholla; that is, cactus is a word with a broader meaning than cholla:

cholla: arborescent cacti having very spiny cylindrical stem segments; southwestern United States and Mexico
cactus: any succulent plant of the family Cactaceae native chiefly to arid regions of the New World and usually having spines

cholla (noun)	cactus (noun)
arborescent cacti having very spiny cylindrical stem segments; southwestern United States and Mexico	any succulent plant of the family Cactaceae native chiefly to arid regions of the New World and usually having spines