spine

Everyday

1. The row of small bones (vertebrae) down the middle of your back, also called the backbone. tree →
2. A sharp, pointed part on an animal or plant, like the spines of a hedgehog or a cactus. tree →
3. The back edge of a book, where the pages are joined and the title is usually printed. tree →
4. Courage: having the spine to do something. tree →

In the lessons

In science, the spine protects the spinal cord, which carries messages between the brain and the body. Animals with a backbone are vertebrates (fish, amphibians, reptiles, birds, mammals); animals without are invertebrates (insects, worms, slugs, jellyfish). In safety, sitting well and lifting with your legs protects your spine; never move someone who may have hurt their neck or back — call for help. In libraries, the spine shows the title so you can find books on a shelf. Phrases: "spine-chilling" (scary), "a book spine", "cactus spines", "shivers down my spine".

Examples

• Your spine is made of 33 small bones. tree →
• Hedgehogs have sharp spines. tree →
• Careful — cactus spines are prickly. tree →
• Read the title on the spine of the book. tree →
• Animals with a spine are called vertebrates. tree →
• The ghost story sent shivers down my spine. tree →
• Sit up straight to look after your spine. tree →
• A fish's spine runs from its head to its tail. tree →
• They climbed up the dragon's side and dumped the children down on his icy spine, with their backs against the North Pole. tree →

Note

Countable: a spine, spines. Adjective: spinal (spinal cord). "Spineless" means without a backbone or, about people, not brave. Most adults have 33 vertebrae, some of which join together. Hedgehog spines are hollow hairs; porcupines have quills.