Irish potato and Root vegetable

Irish potato noun - An edible tuber native to South America; a staple food of Ireland.

Root vegetable and Irish potato are semantically related. In some cases you can use "Root vegetable" instead a noun phrase "Irish potato".

Root vegetable noun - Any of various fleshy edible underground roots or tubers.

Irish potato and root vegetable are semantically related. Sometimes you can replace phrase "Irish potato" with "Root vegetable", this phrases are similar.