• WordNet 3.6
    • n sacrum wedge-shaped bone consisting of five fused vertebrae forming the posterior part of the pelvis; its base connects with the lowest lumbar vertebra and its tip with the coccyx
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Webster's Revised Unabridged Dictionary
    • n Sacrum (Anat) That part of the vertebral column which is directly connected with, or forms a part of, the pelvis.☞ It may consist of a single vertebra or of several more or less consolidated. In man it forms the dorsal, or posterior, wall of the pelvis, and consists of five united vertebræ, which diminish in size very rapidly to the posterior extremity, which bears the coccyx.
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Century Dictionary and Cyclopedia
    • n sacrum A compound bone resulting from the ankylosis of two or more vertebræ between the lumbar and the coccygeal region of the spine, mostly those which unite with the ilia; the os sacrum. In man the sacrum normally consists of five sacral vertebræ thus united, and is the largest, stoutest, and most solid part of the vertebral column, forming a curved pyramidal mass with the base uppermost, the keystone of the pelvic arch, wedged in posteriorly between the ilia, with which it articulates or unites by the sacro-iliac synchondrosis, all the body above being supported, so far as its bony basis is concerned, by the sacrum alone. A similar but narrower, straighter, less pyramidal and more horizontal sacrum composed of a few bones (usually two to five, sometimes ten) characterizes Mammalia at large. (See sacral.) In birds a great number of vertebræ are ankylosed to form the sacrarium or so-called sacrum, and a large number unite with the ilia, but the greater number of these are borrowed from both the lumbar and the coccygeal series, and in this class it has been proposed to limit the term sacrum to the few (three to five) vertebræ which are in special relation with the sacral plexus. (See urosacral.) In some reptiles or batrachians a single ribbearing vertebra may be united with the ilia, and so represent alone a sacrum. Also called rump-bone. See also cuts under epipleura, Ornithoscelida, pelvis, Ichthyosauria, Dinornis, pterodactyl, sacrarium, and marsupial.
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Chambers's Twentieth Century Dictionary
    • n Sacrum sā′krum a triangular bone situated at the lower part of the vertebral column (of which it is a natural continuation), and wedged between the two innominate bones, so as to form the keystone to the pelvic arch
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Webster's Revised Unabridged Dictionary
NL., fr. L. sacer, sacred, os sacrum, the lowest bone of the spine
Chambers's Twentieth Century Dictionary
L. sacrum (os, bone), sacred.


In literature:

Down with him qui Deae sacrum vulgarit arcanae.
"The Virginians" by William Makepeace Thackeray
For example, the sacrum is in early life made up of five distinct bones which later unite into one.
"A Practical Physiology" by Albert F. Blaisdell
The white race, according to Bacarisse, has the broadest sacrum, the yellow race coming next, the black race last.
"Studies in the Psychology of Sex, Volume 4 (of 6)" by Havelock Ellis
Sed para irato deo sacrum idoneum et monstrum saevum ex patria tua agetur.
"Latin for Beginners" by Benjamin Leonard D'Ooge
The sympathetic ganglia of the pelvis consist of five pairs, which are situated upon the surface of the sacrum.
"The People's Common Sense Medical Adviser in Plain English" by R. V. Pierce
The sacrum, for instance, is created by the fusing together of several vertebrae into one bone for the sake of greater strength and stability.
"Vitality Supreme" by Bernarr Macfadden
I saw one or two instances of perforation of the sacrum.
"Surgical Experiences in South Africa, 1899-1900" by George Henry Makins
That part of the ilium which abuts against the sacrum.
"Surgical Anatomy" by Joseph Maclise
He shows the sternum to consist, in the adult, of three parts and the sacrum of five or six.
"Fathers of Biology" by Charles McRae
I have given you quite pointedly and at length, hints on spine and sacrum which cover the territory below the diaphragm.
"Philosophy of Osteopathy" by Andrew T. Still

In news:

The gyroscopic movement of the sacrum is a primary function of sacroiliac motion during a normal gait cycle.
Evaluating the sitting patient from behind, palpate the sacrum for fascial barriers.
Apollo 's Fire, Cleveland's baroque orchestra, will be busy beginning Wednesday with eight local performances of Sacrum Mysterium: A Celtic Christmas as well as its dramatic interpretation of the Christmas favorite Handel's Messiah.
It sits between the sacrum and the iliac bone (thus the name "sacroiliac" joint).
Figure B shows the reptile 's sacrum, pelvis and associated egg.