Definition of radius
- a truck with a short turning radius
Measure the radius of the circle.
a radius of 10 inches
The new museum is expected to draw people from a wide radius.
There are three restaurants within a one-block radius of our apartment.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radius.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
First Known Use: 1578See Words from the same year
: a straight line from the center of a circle or sphere to any point on the outer edge; also : the length of this line
: an area that goes outward in all directions from a particular place
medical : the bone in the lower part of your arm on the same side as your thumb
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