Meaning

noun southern European plant having spiny leaves and purple flowers cultivated for its edible leafstalks and roots

noun only parts eaten are roots and especially stalks (blanched and used as celery); related to artichokes

originFrom Middle English cardoun, from Old French cardon, from Late Latin cardōnem, from Latin cardus, alternative form of carduus (“thistle”). Respelled on analogy of -oon nouns. Doublet of cardon and chard.

Etymology from Wiktionary, CC BY-SA 3.0