脊椎|せきついsekitsui[0]heiban (flat)

1. noun, anatomyspine; vertebral column; spinal column; backbone
2. noun, anatomyvertebra

• Synonym背骨せぼねNeutralEveryday word for the backbone, common in speech; also used figuratively for the core of something. 「脊椎」 sounds more medical or biological.
• Synonym脊柱せきちゅうWrittenMedical term for the spinal column as a whole. 「脊椎」 can mean the whole spine or the individual vertebrae that make it up.

In everyday speech use 「背骨」; 「脊椎」 is the medical and biological term for the spine or the vertebrae that make it up, as in 「脊椎動物」; for the spinal column as a whole, 「脊柱」 also works.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 脊柱せきちゅうを構成こうせいする骨ほね。