Written by the Fiveable Content Team • Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 exam•Written by the Fiveable Content Team • Last updated September 2025
Definition
A cone is a three-dimensional geometric shape with a circular base and a pointed top, called an apex. The surface of a cone consists of curved sides that meet at the apex.
Related terms
Cylinder: A cylinder is another three-dimensional shape, but instead of having a pointed top like a cone, it has two parallel circular bases connected by curved sides.
Frustum: A frustum is what you get when you slice off the top portion of a cone or pyramid parallel to its base. It resembles a truncated version of the original shape.
A sphere is a perfectly round three-dimensional object where all points on its surface are equidistant from its center. Think of it as resembling a basketball or planet Earth.