Hottentot's bread vs elephant's-foot

Hottentot's bread and elephant's-foot both are nouns.

Word	Noun	Adjective	Verb	Adverb
Hottentot's bread	Yes	No	No	No
elephant's-foot	Yes	No	No	No

Hottentot's bread (noun)	elephant's-foot (noun)
thick edible rootstock of elephant's-foot	any plant of the genus Elephantopus having heads of blue or purple flowers; America
	South African vine having a massive rootstock covered with deeply fissured bark