How to say "spine" in Japanese

Choosing the right word

背骨せぼねCommon
nounThe physical backbone of a person or animal, the column of bones running down the back. The everyday word when talking about the spine as a body part.
私の背骨せぼねの痛いたみはひどくなっています。↗
The pain in my back is getting worse.
背筋せすじCommon
nounThe line or stretch of the backbone, often of posture, as in a straight or straightened back. Refers to the spine viewed as a line rather than as bones.
それを見みてうれしくて背筋せすじがぞくぞくした。↗
The sight sent chills of delight up my spine.
刺とげJLPT N1approx.Common
nounNot the body part at all: this is a sharp point, a thorn or prickle. Its 'spine' sense covers stiff pointed structures on plants, fish, or animals.
どのバラにもとげがあるように人生じんせいには悲かなしみがある。↗
Life has its sorrows, as every rose has its thorns.
脊椎せきついCommon
nounThe vertebral column as an anatomical structure. The technical or medical word for the spine, the natural choice in scientific, medical, or formal discussion of the vertebrae.
背せJLPT N5approx.Common
nounHere it is the spine of a book, the bound edge you see on a shelf. For the body part this word means the back in general, so use 背骨 instead.
彼かれはいすの背せにもたれている。↗
He is leaning on the back of the chair.

For the body part, use 背骨 or 背筋; 脊椎 is the anatomical/medical term; 刺 covers spines on plants or animals; and 背 refers to the spine of a book.

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

Japanese equivalents

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