Definition

The distance around the edge of a circle or the outer boundary of a shape.

Example

To find the circumference of a circle, you can use the formula 2πr, where r is the radius.

Conversation

Have you ever tried to measure the circumference of a circle?

No, I haven't! How do you do that?

It's actually pretty simple; you just multiply the diameter by pi.

That sounds easy enough! I might give it a try.

Synonyms & Antonyms

Root Explanation

Circumference is formed from "circum-" (meaning around) and "ferre" (meaning to carry). The word describes the distance around a circle, as if it is carrying the boundary of the shape.

Memory Tip

Think of something that 'carries' ('ferre') the distance 'around' ('circum-') a circle — that's what circumference means.

Visually Confused Words