spinal column; spine; vertebral column
Anatomical term for the spine; used in medical and formal contexts. In everyday conversation, 背骨 (せぼね) is more common.
The spinal column is an important skeletal structure that supports the body.
The doctor checked the curvature of the spine on the X-ray.
脊柱 is a strictly anatomical term for the vertebral column, unlike バックボーン, which is mainly used metaphorically for emotional strength or network cores.
Standard kanji spelling for the anatomical term.
Compound of 脊 (せき, 'spine') and 柱 (ちゅう, 'pillar'). The exact historical derivation is uncertain, but the kanji composition transparently conveys the meaning of 'spinal pillar'.