# Meaning of *radius* in English:

## radius^{}

Translate radius into Spanish

### nounplural noun radii/ˈreɪdɪʌɪ/ , plural noun radiuses

1A straight line from the centre to the circumference of a circle or sphere.

*‘Thus, the area of a circle is equal to half of the product of the radius and the circumference.’**‘He calculates the side of a regular pentagon in terms of the radius of the circumscribed circle.’**‘Recall that given a circle of radius r, the circumference is 2pr.’**‘Note that this curvature is the inverse of the radius of a circle tangent to the neutral line at this point.’**‘David Gregory used p/r for the ratio of the circumference of a circle to its radius.’**‘The hexagon is a function between the radius and circumference of the circle, and is a naturally occurring form in nature.’**‘A circle and square have an equal area only if the ratio between a side of the square and a radius of the circle equals the square root of pi.’**‘It states that the centre of gravity of a semicircle divides the radius in the ratio 3: 7.’**‘A circle of radius 6 is circumscribed by a square of side-length 12.’**‘Given an angle CAB draw a circle with centre A so that AC and AB are radii of the circle.’**‘The particular tablet which interests us here investigates how to calculate the radius of a circle through the vertices of an isosceles triangle.’**‘And, if anything, I'm quite nearly positive that Lancome is the guy who discovered the constant ratio of a circle's radius to its circumference.’**‘Because the slices are thin, the height of the rectangle is approximately the radius, r, of the circle.’**‘Company officials like to say that Rhino can go beyond high-school geometry, beyond straight lines and radiuses.’**‘The radii of the given circles and n must stand in a certain relationship for the chain to close on itself.’**‘So the radius of the sphere will be 1 and its surface area will be 4 Pi.’**‘In the introduction he pointed out that a plane was a special case of a spherical surface, that is a sphere with infinite radius.’**‘The point P is on the circumference of the circle of radius b.’**‘Users can measure the distance of vertices/edges/faces, the angle of edges/faces, and the radii and diameters of circles.’**‘The inverse of the radius of the circle equals the curvature in radians/m.’*

- 1.1A radial line from the focus to any point of a curve.
*‘These apply to clear zones on the outside of horizontal curves with a radius of 900 m or less.’**‘Key factors to meet the new criteria include the length and width of runways, the width and curve radii of taxiways, and also the airport's pavement loading limits.’**‘Second, this lightweight insert extends the bullet nose and accommodates use of a longer ogive - the radius of the curve of the bullet tip.’**‘The curve radii and crossfall of the road are measured and fed through algorithms from the Austroads Rural Road Design guide to generate a suggested advisory speed for all points along the road.’**‘The upper three curves are the pore radii for the three systems, whereas the lower three are the corresponding standard deviations of the upper curves.’**‘A minimum curve radius of 5 feet is suggested for 1/2-inch-diameter strand.’**‘Because of the very mountainous terrain and the need for very shallow radius curves, most of the route will be in tunnels, with consequent heavy civil engineering costs.’**‘The front rolled edge and curved radius of this striking two-tiered kitchen island can only be accomplished in solid surface material such as granite or Corian (tm).’*

- 1.2The length of the radius of a circle or sphere.
*‘The cone shaped tip is just under one micrometer in length and has a radius of a few nanometers at its apex.’**‘Interestingly, though the analysis points to a ball with an average radius of 1.584 inches, the measured radius of a real baseball is 1.452 inches.’**‘Stephenson, who constructed both projects, believed that gradients should be less than 1 percent and that curves should have very wide radii of at least a kilometre.’**‘As skaters pull their arms in, their radius decreases and they spin faster.’*

- 1.3A specified distance from a centre in all directions.
*‘there are plenty of local pubs within a two-mile radius’**‘It seems sensible to find somewhere with no population centres within a two-mile radius - like offshore.’**‘The department has acquired legal powers to close all footpaths within a two-mile radius of any free-range poultry farms.’**‘Teams divided into four groups, combing through a two-mile radius searching for any clue of what might have happened.’**‘The Ride Safe program provides rides for students, staff and faculty members from the Student Life Centre to their homes within a certain radius around campus.’**‘A check of directories shows 37 hotels and motels within a three-mile radius of Florence and LaSalle.’**‘Tests results Tuesday showed that all 20 farms within a two mile radius of the original infected farm were negative for avian influenza.’**‘We do not allow students who live within a five-mile radius to use their cars to come to college.’**‘Those deemed more at risk of exposure are those who lived within a one-kilometer radius of the factory for more than 20 years between 1962 and 1987.’**‘Police are investigating links between the arson attack on December 27 and another three within a half-mile radius over the last few days.’**‘He concluded: ‘This year, I will enter half a dozen local races, all within a radius of 50 miles, and hope to do pretty well.’’**‘It should be known in this connection that according to the relevant law, no structure of any kind can be built within a radius of 100 metres of any registered national monument.’**‘But one recommendation to come out of it was that masts should not be located within a radius of 500 metres of schools and homes.’**‘B & Bs within a three-mile radius of the town were full.’**‘The IT professionals usually look out for areas surrounding a radius of 9 km from City Railway Station.’**‘To calculate a radius for each hospital's market area, we limited radii to a range between 10 and 35 miles.’**‘The explosions could reach a radius of 25 meters.’**‘I spent half a century here, most of it within the confines of a small radius.’**‘Day said location is key when making an investment and believes investors should focus on the coastal strip within a 10-mile radius of the city.’**‘Once Keaton laughed so hard he scared all the birds within a ten-foot radius out of their perches.’**‘At half-mile intervals, they stop and count the birds they see or hear within a radius of a quarter mile.’*

2Anatomy

The thicker and shorter of the two bones in the human forearm.Compare with ulna*‘Common osteoporotic fracture sites include the vertebrae, the hip, the distal radius of the forearm, and the proximal humerus.’**‘Scaphoid fractures are rare children and the elderly because of the relative weakness of the distal radius compared with the scaphoid in these age groups.’**‘Abduction is movement of the hand away from the body as the proximal carpal bones move medially on the radius.’**‘He also had tenderness bilaterally over the distal radius and ulna, and anterior tibia.’**‘Bone mineral density was measured at the lumbar spine, radius, hip and femoral neck.’*

- 2.1Zoology The bone in a vertebrate's foreleg or a bird's wing that corresponds to the radius in a human being.
*‘For example, the radius, one of the lower bones of the foreleg, became much broader.’**‘As is usual in chelonioids, the radius is notably longer than the ulna.’**‘In the equid foreleg, radius and ulna are united, and the ulna is greatly reduced so that all weight is born on the radius.’**‘The humerus, radius, and ulna of Adriosaurus appear to be slightly wider than those of the current specimen, but this is probably a result of crushing.’**‘To fit a horse radius into a human forearm would require a physique to rival Popeye.’*

- 2.2Entomology Any of the main veins in an insect's wing.

3Zoology

A radially symmetric feature in an echinoderm or coelenterate, e.g. an arm of a starfish.

### verbverb radiuses, verb radiusing, verb radiused

[with object]Give a rounded form to (a corner or edge)

*‘Brian carefully radiused all the sharp edges and corners’**‘the radiused edges feel sleek and unobtrusive in the hand’**‘The carry bevel package is subtle, radiused by hand using emery sticks, with the sharp edges are gently broken, not belt-sanded into oblivion.’**‘All of the outer edges of the handle are radiused, making for a comfortable grip.’**‘Brian carefully radiused all the sharp edges and corners, blending them gently by hand with file strokes.’**‘I used a 1/2-inch dry-grind diamond router bit to radius the top edges of the counter.’**‘Their pleasantly radiused shape along with the secure pocket clip make this one of the most carry friendly folders I've ever used.’**‘The only negative on this sixgun is that the backstrap is not radiused quite right where it bolts to the frame on both sides of the hammer.’**‘The sight was nicely radiused to match the trigger group and the two holes aligned just so.’**‘After checkering the main spring housing at 25 lpi, it was fit and blended into the frame with the bottom corner radiused.’**‘The ejector is a long Commander style, with the nose radiused.’**‘These flexible wings also blend successive passes and radius the outside edges of the skate lane to prevent ski tips from catching.’**‘In place of crisp corners, radiused edges - as in Tokyo Prada - create the illusion of a jointless architecture.’**‘Its exactly the same width as the green perspex panel above it, with matching radiused corners.’**‘The porte-cochere piers are composed of granite bases, banded brickwork with 1-inch radiused returns, and limestone caps.’**‘You can use a tube flange feature to put a radiused edge on an opening in a sheet-metal part and simultaneously extend it as a tube.’**‘The bottom rolls into the hull sides with a radiused turn rather than a sharp corner-like edge and there is long wine glass-shaped keel integral with the hull.’**‘The tool has a radiused ridge for cutting and edge sealing with the shape of the ridge similar to the shape desired for the edge seal.’**‘A complete set would include a right and left pair, a ‘topping’ plane for the top, and radiused versions for curved sections.’**‘The lock's radiused, arc-shaped design permits maximum surface contact with the blade's tang.’**‘A radiused thumbhole is used to access the blade and, once again, a liner-lock secures it in place.’**‘It is usual for the bar to have a suitable dimensional radiused groove, machined along its length to mould the penetration bead to a desired geometrical shape.’*

**Origin**

Late 16th century (in radius (sense 2 of the noun)): from Latin, literally ‘staff, spoke, ray’.

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