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n. 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.

n. The final fused vertebrae at the base of the spine.

n. The end of the vertebral column beyond the sacrum in man and tailless monkeys. It is composed of several vertebræ more or less consolidated.

n. In human anatomy, the part of the spinal column consisting of the last four bones, the caudal vertebræ or tail-bones, which are stunted and usually ankylosed together. See cut under skeleton.

n. In comparative anatomy and zoology, the caudal vertebræ, when few and small, or ankylosed together; the bony tail itself, when short, as in a bird.

n. the end of the vertebral column in humans and tailless apes

"Also note how much longer and more solid the sacrum (with its attached bone, called the coccyx [2]) is in the male pelvis."

os    bone   

coccyges   

coccygectomy    coccygeal   

tailbone   

tailbone    mideyebrow    perineum    sacrum    scrotum    pubis    scapulae    chiropractor    calcis    braincase