SACRUM

sacrum

(noun) 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

Source: WordNet® 3.1

Etymology

Noun

sacrum (plural sacra or sacrums)

(anatomy) A large triangular bone at the base of the spine, located between the two ilia (wings of the pelvis) and formed from vertebrae that fuse in adulthood.

Anagrams

• Marcus

Source: Wiktionary

sa"crum, n.; pl. sacra (. Etym: [NL., fr. L. sacer sacred, os sacrum the lowest bone of the spine.] (Anat.)

Definition: That part of the vertebral column which is directly connected with, or forms a part of, the pelvis.

Note: 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.

Source: Webster’s Unabridged Dictionary 1913 Edition