white potato vs murphy

white potato and murphy both are nouns.

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

As nouns, white potato and murphy are synonyms defined as:

white potato and murphy: an edible tuber native to South America; a staple food of Ireland

Other synonyms of white potato include Irish potato, potato, spud, tater.

white potato (noun)	murphy (noun)
an edible tuber native to South America; a staple food of Ireland	an edible tuber native to South America; a staple food of Ireland
annual native to South America having underground stolons bearing edible starchy tubers; widely cultivated as a garden vegetable; vines are poisonous