radius
noun/ˈreɪdiəs/
/ˈreɪdiəs/
(plural radii
/ˈreɪdiaɪ/
/ˈreɪdiaɪ/
)- a straight line between the centre of a circle and any point on its outer edge; the length of this line compare diameterTopics Maths and measurementc1
- a round area that covers the distance mentioned from a central point
- within a… radius They deliver to within a 5-mile radius of the store.
- Doctors wish to examine everyone living within a 10-mile radius of the factory.
- (anatomy) the shorter bone of the two bones in the lower part of the arm between the elbow and the wrist, on the same side as the thumb see also ulnaTopics Bodyc2
Word Originlate 16th cent. (in sense (3)): from Latin, literally ‘staff, spoke, ray’.
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radius