Cone Names a Shape, a Pine Fruit and a Cell in Your Eye
A cone is a solid tapering to a point. The word covers geometry, botany and the retina.
A cone is a solid with a circular base tapering to a point. The word runs from geometry into biology twice over: a *pine cone* is named for the shape, and the *cones* of the retina are the cone-shaped cells that detect colour, as opposed to the rod-shaped cells that work in dim light. Human eyes have three types of cone, tuned to different wavelengths, which is why we see colour the way we do — some birds have four.
- A tapering solid. *A traffic cone.*
- A pine cone. *A fir cone.*
- A retinal cell. *Rods and cones.*
- An ice cream cone. *A cone.*
- Greek — *konos*. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | cone | A cone. |
| Plural | cones | Cones. |
| Adjective | conical | Conical. |
| Related | conifer | A conifer. |
| Greek | konos | A cone. |
- The volume of a cone is one third.Geometry.
- Pine cones littered the path.Botany.
- Cones detect colour.Vision.
Rods and cones
- Rods work in dim light but give no colour
- Cones need brighter light and detect colour
- Humans have three cone types, tuned to different wavelengths
- Many birds have four, including one for ultraviolet
- That is why colour vision differs so much between species
Greek *konos*, a cone or pine cone, through Latin *conus*.
Why are retinal cells called cones?
Because of their shape. They are distinguished from the rod-shaped cells that handle dim light.
Do all animals see colour the same way?
No. Humans have three cone types. Many birds have four, including one sensitive to ultraviolet light.