In geometry, a diameter of a circle is any straight line segment that passes through the centre of the circle and whose endpoints lie on the circle. It can also be defined as the longest chord of the circle.

The diameter of a circle is a line that passes through the center and meets the circumference at opposite ends. It is twice as long as the radius of the circle.

Oct 22, 2025 · From clear definitions and real-life examples to FAQs and a quick quiz, explore everything you need to know about diameter in this guide.

The meaning of DIAMETER is a chord passing through the center of a figure or body. How to use diameter in a sentence.

Apr 15, 2025 · The diameter of a circle is the distance straight across the circle from one side to the other at its center. Depending on what other information you have about the circle, there are a few …

Jul 23, 2025 · To calculate the diameter of a circle we use the formula D = 2r. The diameter of any circle is the longest chord of the circle, that passes through the centre of the circle.

The diameter of a circle is the length of the line through the center and touching two points on its edge. In the figure above, drag the orange dots around and see that the diameter never changes.