cactus: [17] Cactus comes via Latin from Greek káktos, which was the name of the cardoon, a plant of the thistle family with edible leafstalks. Cactus originally had that meaning in English too, and it was not until the 18th century that the Swedish botanist Linnaeus applied the term to a family of similarly prickly plants. [cactus etymology, cactus origin, 英语词源]