piercing appendages in the proboscis of scorpions and spiders, 1831, plural of Modern Latin chelicera, from Greek khēlē "crab claw, talon, pincers; cloven hoof of cattle, horse's hoof," metaphorically "surgical forceps, hooked needle, crochet needle, notch of an arrow," a word of uncertain origin with no agreement on ulterior connections (according to Watkins, related to keras "horn," from PIE root *ker- (1) "horn; head"). Earlier chelicer (1835), from French chélicère.