white potato vs starches

white potato and starches both are nouns.

Word	Noun	Adjective	Verb	Adverb
white potato	Yes	No	No	No
starches	Yes	No	No	No

As nouns, starches is a hypernym of white potato; that is, starches is a word with a broader meaning than white potato:

white potato: an edible tuber native to South America; a staple food of Ireland
starches: foodstuff rich in natural starch (especially potatoes, rice, bread)

Other hypernyms of white potato include solanaceous vegetable, root vegetable.

white potato (noun)	starches (noun)
an edible tuber native to South America; a staple food of Ireland	foodstuff rich in natural starch (especially potatoes, rice, bread)
annual native to South America having underground stolons bearing edible starchy tubers; widely cultivated as a garden vegetable; vines are poisonous