spine

American  

[spahyn] / spaɪn /

noun

1. the spinal or vertebral column; backbone.

2. any backbonelike part.

3. a stiff, pointed process or appendage on an animal, as a quill of a porcupine, or a sharp, bony ray in the fin of a fish.

4. something, as a quality or trait, that constitutes a principal strength; resolution; stamina; backbone.

   a situation that would test a person's spine.

5. a ridge, as of ground or rock.

6. a sharp-pointed, hard or woody outgrowth on a plant; thorn.

7. Bookbinding. the back of a book cover or binding, usually indicating the title and author.

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spine British  

/ spaɪn /

noun

1. the spinal column

2. the sharply pointed tip or outgrowth of a leaf, stem, etc

3. zoology a hard pointed process or structure, such as the ray of a fin, the quill of a porcupine, or the ridge on a bone

4. the back of a book, record sleeve, etc

5. a ridge, esp of a hill

6. strength of endurance, will, etc

7. anything resembling the spinal column in function or importance; main support or feature

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spine Scientific  

/ spīn /

1. See vertebral column

2. Any of various pointed projections, processes, or appendages of animals.

3. A sharp-pointed projection on a plant, especially a hard, narrow modified leaf, as on a cactus, that is adapted to reduce water loss.

4. Compare thorn See more at leaf

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Other Word Forms

• spined adjective
• spinelike adjective

Etymology

Origin of spine

1400–50; late Middle English < Latin spīna thorn, backbone

Explanation

Your spine is your backbone. When you sit and stand with your spine straight, people will compliment you on your good posture. Besides being the basic part of a vertebrate's skeleton, a spine is also a sharp spike, like the spines on a sea urchin or a cactus. Another kind of spine is the "backbone" of a book, the part of its cover that you can read when the book is on a bookshelf. Spine comes from the Latin spina, which also means both "backbone" and "thorn."

Example Sentences

Moses’s life forms the exhibition’s spine, and it was a rather hard one.

From The Wall Street Journal • Apr. 11, 2026

It’s tough on his spine but also results in long drives and low scores.

From Los Angeles Times • Apr. 8, 2026

“Can’t Stop” starts with an uncharacteristically spare riff by Frusciante’s standards, and coupled with Chad Smith’s inerrant rhythm, we have the song’s spine.

From Salon • Apr. 4, 2026

The researchers also examined nerve fibers within the spine.

From Science Daily • Mar. 23, 2026

Goose bumps popped up on my arms and chills ran down my spine, shaking me to the core.

From "Summer of the Mariposas" by Guadalupe García McCall

Related Words

• bone
• vertebrae