A Book's Spine Is Named After the Backbone
The spine is the backbone, and by extension anything that supports or projects. Books, cacti and hedgehogs all have them.
The spine is the column of bones down the back, and by extension the bound edge of a book or a sharp projection on a plant or animal. Latin *spina* meant both a thorn and a backbone, and English inherited both senses at once — which is why a hedgehog's spines and a human spine are the same word, and why a book's spine is named for the part that holds it together. *Spineless* means lacking courage, treating the backbone as the seat of resolve.
- The backbone. *A curved spine.*
- A book's bound edge. *The spine of the book.*
- A sharp projection. *Cactus spines.*
- Spineless — lacking courage. *Spineless.*
- Latin — *spina*, thorn or backbone. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | spine | The spine. |
| Plural | spines | Spines. |
| Adjective | spinal | Spinal. |
| Adjective | spiny | Spiny. |
| Latin | spina | A thorn. |
- The title is printed on the spine.Books.
- A hedgehog raises its spines.Animals.
- Spina meant thorn and backbone.Etymology.
The human spine
- Cervical — seven vertebrae in the neck
- Thoracic — twelve, attached to the ribs
- Lumbar — five in the lower back
- Sacrum and coccyx — fused vertebrae at the base
- Giraffes have seven cervical vertebrae too, just much longer ones
Old French *espine*, from Latin *spina*, a thorn or the backbone.
Why do a cactus and a person both have spines?
Latin spina meant both thorn and backbone, and English took over both senses of the one word.
How many neck vertebrae does a giraffe have?
Seven, the same as a human. They are simply far longer.