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Related to radii: ionic radii, Atomic radii


A plural of radius.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Mathematics) a plural of radius
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˈreɪ di əs)

n., pl. -di•i (-diˌaɪ)
1. a straight line extending from the center of a circle or sphere to the circumference or surface: The radius of a circle is half the diameter.
2. the length of such a line.
3. any radial or radiating part.
4. a circular area having an extent determined by the length of the radius from a given or specified central point: every house within a radius of 50 miles.
5. a field or range of operation or influence.
6. extent of possible operation, travel, etc., as under a single supply of fuel.
7. the bone of the forearm on the thumb side.
8. a corresponding bone in the forelimb of other vertebrates.
[1590–1600; < Latin: staff, rod, spoke, beam, ray1]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.


pl de radius
English-Spanish/Spanish-English Medical Dictionary Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.
References in classic literature ?
But, inasmuch as it is equally necessary to take into account the deviation which the rotary motion of the earth will impart to the shot, and as the shot cannot reach the moon until after a deviation equal to 16 radii of the earth, which, calculated upon the moon's orbit, are equal to about eleven degrees, it becomes necessary to add these eleven degrees to those which express the retardation of the moon just mentioned: that is to say, in round numbers, about sixty-four degrees.
"The screw consists of an axis of hollow brass tube, eighteen inches in length, through which, upon a semi-spiral inclined at fifteen degrees, pass a series of steel wire radii, two feet long, and thus projecting a foot on either side.
The latter savant had, one day, gone so far as to propose to him the following problem: Given the number of miles travelled by the doctor in making the circuit of the Globe, how many more had his head described than his feet, by reason of the different lengths of the radii?--or, the number of miles traversed by the doctor's head and feet respectively being given, required the exact height of that gentleman?
* I have often noticed a peculiar movement of the fire-flies ; - they will collect in a body and fly off, from a common centre, into innumerable radii.
The planetary masses and radii of these exoplanets can be used to infer their mean density, but not their exact chemical composition and structure.
A critical part of accurately forecasting tropical cyclones (TCs) is estimating the storm wind radii as a gauge of storm structure and size.
Thrombocytopenia absent radius (TAR) syndrome is a rare genetic condition, characterized by bilateral absence of the radii while both thumbs are present, and thrombocytopenia.
Such exit radii are not usually there by design but are caused by periodic maintenance and/or gauging.
[11] used dry radii, which were collected from two universities in France, to measure the angle between the flat surface and the line connecting the starting point and end point (CSSO) at the lateral and intermediate sections.
Radii is a recently launched social app that connects people in proximity.
Important information of location, number and direction of nutrient foramina in human radii provides great aid in many surgical and clinical cases like bone grafts and internal fixation devices.