spine

spine — noun

1. the connected set of bones that extends from the base of the skull to the lower

1.nounB1
Definition

the connected set of bones that extends from the base of the skull to the lower back, forming a central column that supports the body and encloses the spinal cord

Example

Amihan injured her spine in a car accident last year.

The doctor looked at the X-ray of Lan's spine and found no damage.

collocation: spine X-ray / doctor examines spine

Common collocations
  • spine injury
  • spine surgery
  • curvature of the spine
  • lower spine
  • fractured spine
Synonyms
  • backbone

    less formal, used in everyday speech and figuratively

  • spinal column

    fully medical term, less common in casual conversation

Usage Note

Many everyday phrases use back instead of spine (e.g., back pain, back injury), but spine is the standard medical and anatomical term.

Common Mistakes

My spine hurts when I bend.
My back hurts when I bend.
For general aches, back is more natural; spine is clinical and refers specifically to the bone column.

2. a stiff, pointed growth that sticks out of the skin or surface of some animals a

2.nounB2
Definition

a stiff, pointed growth that sticks out of the skin or surface of some animals and plants, serving as a defence against threats

Example

Felix touched the cactus and a spine got stuck in his finger.

collocation: cactus spine / spine stuck in finger

A hedgehog curls into a ball so that its spines point out in every direction.

collocation: hedgehog spines / spines point outward

Common collocations
  • cactus spine
  • hedgehog spine
  • sharp spine
  • raise spines
  • spine-covered
Synonyms
  • thorn

    used mainly for plants, particularly roses; softer connotation

  • quill

    specifically for porcupines; longer and hollow

Usage Note

Spine in this sense is close in meaning to thorn, but spine is stiffer and often refers to structures on animals (hedgehog, porcupine) as well as plants. Thorn typically refers only to plants.

Common Mistakes

A rose has many spines.
A rose has many thorns.
Thin, sharp outgrowths on rose stems are called thorns in everyday English; spine is more common for cacti and animals.

3. the narrow outer edge where a book's front cover meets its back cover, holding t

3.nounB1
Definition

the narrow outer edge where a book's front cover meets its back cover, holding the pages together and typically displaying the title on its surface

Example

Renata read the title on the book spine to find it on the shelf.

collocation: title on the spine

The librarian carefully repaired the torn spine of an old novel.

Common collocations
  • book spine
  • spine of the book
  • spine label
  • cracked spine
  • spine title
Synonyms
  • book back

    much less common; most English speakers say spine

Word family

  • spinal
    adjectiveB2
  • spineless
    adjectiveC1
  • spiny
    adjectiveC1

Synonym discussion

Sense: noun/1

All three terms relate to the central bony structure of the back, but they differ in scope and register. Spine is the most common everyday word for the whole structure; it works in both casual and medical contexts. Backbone is more informal and is frequently used figuratively (e.g., the backbone of the team); it also sounds less technical when talking about animals. Spinal column is a strictly anatomical term, used by doctors and in textbooks rather than in ordinary conversation. Vertebrae (plural of vertebra) refers to the individual bones that make up the spine, not the whole structure — so saying 'I broke a vertebrae' is precise, while 'I broke my spine' suggests a major injury to the whole column.

backbonespinal columnvertebrae

Common collocations

Nouns

  • spine injury
  • spine surgery
  • spine X-ray
  • spine label

Phrases

  • curvature of the spine
  • fracture of the spine
  • title on the spine

Prepositions

  • spine of [something]

Etymology

LatinFrenchEnglish

Spine comes from the Latin word spina, which originally meant 'thorn' or 'prickle'. The Romans used spina for the backbone because the shape of the vertebrae reminded them of a row of thorns. By the 1400s, English had adopted the word for the bone column, and in the 1500s it also began to refer to the back edge of a book, likely from the image of the spine as the 'backbone' of the book. The plant and animal 'thorn' meaning never disappeared — it survives in the modern sense 2.