noun, plural ra·di·i [rey-dee-ahy] /ˈreɪ diˌaɪ/, ra·di·us·es.
Origin of radius
Examples from the Web for radius
Another requirement was that the Colombian National Police would not be permitted within a 12-mile radius of his prison.Pablo Escobar’s Private Prison Is Now Run by Monks for Senior Citizens|Jeff Campagna|June 7, 2014|DAILY BEAST
These were then spread over a 300-mile radius, covered in ravines, gorges and pine forests.The Bosnia Atrocities, the World’s Greatest Forensic Puzzle|J.P. O’Malley|December 1, 2013|DAILY BEAST
Khazaee was referring to a 25-mile radius travel ban on Iranian diplomats.Iran’s Foreign Minister Loves Facebook Despite Banning It at Home|David Keyes|October 9, 2013|DAILY BEAST
Part of its plan is to have as many suppliers as possible within a 250-mile radius.
People there are born, go to school, get married, grow old, and die within a 50-mile radius.
They were located within a radius of one league of each other and must correspond to the three seen by Moraga.The Aboriginal Population of the San Joaquin Valley, California|Sherburne F. Cook
Pores irregular, roundish, of different sizes; twelve to fourteen on the radius.
Pores regular, circular; eight to nine on the radius of the phacoid shell, two on the breadth of each chamber.
Within a radius of a hundred yards were thirty to forty corpses, mostly Americans.A Company of Tanks|W. H. L. Watson
By-spines (one hundred and fifty to two hundred) very thin, barbed and zigzag, as long as the radius.
British Dictionary definitions for radius
noun plural -dii (-dɪˌaɪ) or -diuses
- any radial or radiating part, such as a spoke
- (as modifier)a radius arm
Word Origin for radius
Word Origin and History for radius
1590s, "cross-shaft," from Latin radius "staff, stake, rod; spoke of a wheel; ray of light, beam of light; radius of a circle," of unknown origin. Perhaps related to radix "root," but Tucker suggests connection to Sanskrit vardhate "rises, makes grow," via root *neredh- "rise, out, extend forth;" or else Greek ardis "sharp point."
The geometric sense first recorded 1610s. Plural is radii. Meaning "circular area of defined distance around some place" is attested from 1953. Meaning "shorter bone of the forearm" is from 1610s in English (the Latin word had been used thus by the Romans).