|—n , pl coccyges|
|a small triangular bone at the end of the spinal column in man and some apes, representing a vestigial tail|
|[C17: from New Latin, from Greek kokkux cuckoo, of imitative origin; from the likeness of the bone to a cuckoo's beak]|
coccyx coc·cyx (kŏk'sĭks)
n. pl. coc·cy·ges (kŏk-sī'jēz, kŏk'sĭ-jēz')
The small triangular bone located at the base of the spinal column, formed by the fusion of four rudimentary vertebrae, and articulating above with the sacrum. Also called tailbone.
|coccyx (kŏk'sĭks) Pronunciation Key
Plural coccyges (kŏk-sī'jēz, kŏk'sĭ-jēz')
A small triangular bone at the base of the spine in humans and apes. It is composed of several fused vertebrae. Also called tailbone.
curved, semiflexible lower end of the backbone (vertebral column) in apes and humans, representing a vestigial tail. It is composed of three to five successively smaller caudal (coccygeal) vertebrae. The first is a relatively well-defined vertebra and connects with the sacrum; the last is represented by a small nodule of bone. The spinal cord ends above the coccyx. In early adulthood the coccygeal vertebrae fuse with each other; in later life the coccyx may fuse with the sacrum. A corresponding structure in other vertebrates, such as birds, may also be called a coccyx.
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