noun (plural vertebrae /-breɪ, -briː/)
In the human spine (or vertebral column) there are seven cervical vertebrae (in the neck), twelve thoracic vertebrae (to which the ribs are attached), and five lumbar vertebrae (in the lower back). In addition, five fused vertebrae form the sacrum, and four the coccyx
early 17th century: from Latin, from vertere 'to turn'
The plural of vertebra is vertebrae (as in the original Latin).