tuber vs wild bean

tuber and wild bean both are nouns.

Word	Noun	Adjective	Verb	Adverb
tuber	Yes	No	No	No
wild bean	Yes	No	No	No

As nouns, wild bean is a hyponym of tuber; that is, wild bean is a word with a more specific, narrower meaning than tuber:

tuber: a fleshy underground stem or root serving for reproductive and food storage
wild bean: nutlike tuber; important food of Native Americans

Other hyponyms of tuber include water chestnut, groundnut, potato bean, Jerusalem artichoke, yam.

tuber (noun)	wild bean (noun)
a fleshy underground stem or root serving for reproductive and food storage	nutlike tuber; important food of Native Americans
	a North American vine with fragrant blossoms and edible tubers; important food crop of Native Americans