backbone

Compared meaning: the spine, the row of bones down the back (noun).

比较义项：脊柱、脊骨（背部中间由一串骨头构成的结构）（名词）。

• spine

  The standard, precise term for this body part, used in both everyday speech and medical contexts, especially about humans and injuries; typical collocations are spine injury, curvature of the spine.

  这是描述该身体部位最标准、精确的说法，日常和医学语境都常用，尤其用于人类和受伤情形；常见搭配有 spine injury（脊柱损伤）、curvature of the spine（脊柱侧弯）。

  He broke two vertebrae in his spine during the fall.

  他摔倒时摔断了脊柱里的两块椎骨。

• backbone 本词

  An older, more general word for the same structure, most typical when classifying animals (defining vertebrates) rather than describing human injuries; sounds less clinical than spine in medical settings.

  这是同一结构的一个更古老、更笼统的说法，最常出现在给动物分类的语境中（用来定义脊椎动物），而不太用来描述人类受伤情况；在医学场合听起来不如 spine 专业。

  Vertebrates are defined as animals that have a backbone.

  脊椎动物的定义就是拥有脊椎骨的动物。

Spine and backbone both name the row of bones down the back. Spine is the standard word in everyday and medical use, especially about injuries. Backbone is older and more general, most typical when classifying animals, like defining vertebrates, and sounds less clinical than spine.

这两个词在字面上都指人或动物背部中间的那条骨头结构，含义很接近，但用法场合不同：spine 是医学和日常语境里最标准、最常用的说法，backbone 则更常出现在给动物分类的语境中。这里不比较 backbone 表示“支柱、骨干”的比喻义（如 the backbone of the economy）。