noun (plural sacra /-krə/ or sacrums)Anatomy
A triangular bone in the lower back formed from fused vertebrae and situated between the two hip bones of the pelvis.
More example sentences
- The spinal column is composed of seven cervical vertebrae, twelve thoracic vertebrae, five lumbar vertebrae, the bony sacrum, and the coccyx.
- The lowest lumbar vertebra articulates with the sacrum, and this in turn with the coccyx.
- Vesalius said that the human sacrum normally has five vertebrae but one of six is by no means rare.
mid 18th century: from Latin os sacrum, translation of Greek hieron osteon 'sacred bone' (from the belief that the soul resides in it).
Definition of sacrum in:
- The US English dictionary