earthnut

American  

[urth-nuht] / ˈɜrθˌnʌt /

noun

1. any of various roots, tubers, or underground growths, as the peanut and the truffle.

2. any of the plants producing these.

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earthnut British  

/ ˈɜːθˌnʌt /

noun

1. Also called: pignut.  a perennial umbelliferous plant, Conopodium majus, of Europe and Asia, having edible dark brown tubers

2. any of various plants having an edible root, tuber, underground pod, or similar part, such as the peanut or truffle

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Etymology

Origin of earthnut

before 900; Middle English erthenote, Old English eorthnutu. See earth, nut