coccyx
Word family nouncoccyxadjectivecoccygeal
coc·cyx /ˈkɒksɪks $ ˈkɑːk-/ noun (plural coccyxes or coccyges /kɒkˈsaɪdʒiːz $ ˈkɑːksə-/) [countableC] technical coccyx• Too much to expect a new pair of arms to grow out of her ribs, or her coccyx to elongate so enormously.• Pain like this after a fall on the coccyx. Origin coccyx (1500-1600) Modern Latin Greek kokkyx “cuckoo”; because it looks like a cuckoo's beak