coccyx

coc·cyx   (kŏk'sĭks)    (click for larger image in new window) n.   pl. coc·cy·ges (kŏk-sī'jēz, kŏk'sĭ-jēz') A small triangular bone at the base of the spinal column in humans and tailless apes, consisting of several fused rudimentary vertebrae. Also called tailbone. [New Latin, from Greek kokkūx, cuckoo, coccyx (from its resemblance to a cuckoo's beak).]

coccyx 

Main Entry: coc·cyx
Pronunciation: 'käk-siks
Function: noun
Inflected Form: plural coc·cy·ges /'käk-s&-"jEz/ also coc·cyx·es /'käk-sik-s&z/
: a small bone that articulates with the sacrum and that usually consistsof four fused vertebrae which form the terminus of the spinal column

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

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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