### Examples

- A truncated cone is called a frustum if the cone is cut by a plane that is parallel to the base.The solid at the bottom is the frustum of the cone.
- A truncated pyramid is called a frustum if the pyramid is cut by a plane that is parallel to the base.

The solid at the bottom is the frustum of the pyramid.

### Etymological Note

The term “frustum” is derived from the Latin word *frustum* meaning “piece” or “bit”.