murphy vs Irish potato

murphy and Irish potato both are nouns.

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

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

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

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

murphy (noun)	Irish potato (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