carrot (n.)
1530s, from Middle French carrotte, from Latin carota, from Greek karoton "carrot," probably from PIE *kre-, from root *ker- (1) "horn, head" (see horn (n.)); so called for its horn-like shape.

Originally white-rooted and a medicinal plant to the ancients, who used it as an aphrodisiac and to prevent poisoning. Not entirely distinguished from parsnips in ancient times. Reintroduced in Europe by Arabs c.1100. The orange carrot, which existed perhaps as early as 6c., probably began as a mutation of the Asian purple carrot and was cultivated into the modern edible plant 16c.-17c. in the Netherlands. Thus the word is used as a color name but not before 1670s in English, originally of red hair.