Meaning & use

radius

noun·Academic

A line segment from a circle's center to its boundary, or the length of that segment.

See it in a sentence

The radius of a circle with diameter 12 centimeters is 6 centimeters.

Set the compass opening to the required radius before drawing the circle.

A note on using this word

Every radius of the same circle has the same length. The plural is radii or radiuses.

Words with a similar meaning

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