radius


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ra·di·us

 (rā′dē-əs)
n. pl. ra·di·i (-dē-ī′) or ra·di·us·es
1. Abbr. r or rad. Mathematics
a. A line segment that joins the center of a circle with any point on its circumference.
b. A line segment that joins the center of a sphere with any point on its surface.
c. A line segment that joins the center of a regular polygon with any of its vertices.
d. The length of any such line segment.
2. A circular area measured by a given radius: every family within a radius of 25 miles of the city center.
3. A bounded range of effective activity or influence: the operating radius of a helicopter.
4. A radial part or structure, such as a mechanically pivoted arm or the spoke of a wheel.
5. Anatomy
a. A long, prismatic, slightly curved bone in humans, the shorter and thicker of the two forearm bones, located on the lateral side of the ulna.
b. A similar bone in many other vertebrates.

[Latin, ray, spoke of a wheel, radius; see ray1.]

radius

(ˈreɪdɪəs)
n, pl -dii (-dɪˌaɪ) or -diuses
1. (Mathematics) a straight line joining the centre of a circle or sphere to any point on the circumference or surface
2. (Mathematics) the length of this line, usually denoted by the symbol r
3. (Mathematics) the distance from the centre of a regular polygon to a vertex (long radius) or the perpendicular distance to a side (short radius)
4. (Anatomy) anatomy the outer and slightly shorter of the two bones of the human forearm, extending from the elbow to the wrist
5. (Zoology) a corresponding bone in other vertebrates
6. (Zoology) any of the veins of an insect's wing
7. (Botany) a group of ray florets, occurring in such plants as the daisy
8.
a. any radial or radiating part, such as a spoke
b. (as modifier): a radius arm.
9. (Mechanical Engineering) the lateral displacement of a cam or eccentric wheel
10. a circular area of a size indicated by the length of its radius: the police stopped every lorry within a radius of four miles.
11. the operational limit of a ship, aircraft, etc
[C16: from Latin: rod, ray, spoke]

ra•di•us

(ˈreɪ di əs)

n., pl. -di•i (-diˌaɪ)
-di•us•es.
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]

ra·di·us

(rā′dē-əs)
Plural radii (rā′dē-ī′) or radiuses
1. A line segment that joins the center of a circle or sphere with any point on the circumference of the circle or the surface of the sphere. It is half the length of the diameter.
2. The shorter and thicker of the two bones of the forearm or the lower portion of the foreleg. See more at skeleton.

radius

One of the two bones of the forearm.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.radius - the length of a line segment between the center and circumference of a circle or sphereradius - the length of a line segment between the center and circumference of a circle or sphere
diam, diameter - the length of a straight line passing through the center of a circle and connecting two points on the circumference
semidiameter - the apparent radius of a celestial body when viewed as a disc from the earth
radius of curvature - the radius of the circle of curvature; the absolute value of the reciprocal of the curvature of a curve at a given point
length - the linear extent in space from one end to the other; the longest dimension of something that is fixed in place; "the length of the table was 5 feet"
2.radius - a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)
straight line - a line traced by a point traveling in a constant direction; a line of zero curvature; "the shortest distance between two points is a straight line"
3.radius - a circular region whose area is indicated by the length of its radius; "they located it within a radius of 2 miles"
region, part - the extended spatial location of something; "the farming regions of France"; "religions in all parts of the world"; "regions of outer space"
4.radius - the outer and slightly shorter of the two bones of the human forearm
forearm - the part of the superior limb between the elbow and the wrist
arm bone - a bone in the arm
5.radius - support consisting of a radial member of a wheel joining the hub to the rimradius - support consisting of a radial member of a wheel joining the hub to the rim
bicycle wheel - the wheel of a bicycle
cartwheel - a wheel that has wooden spokes and a metal rim
support - any device that bears the weight of another thing; "there was no place to attach supports for a shelf"
wagon wheel - a wheel of a wagon
Translations
نِصْف القُطر
poloměrokruh
afstandradius
sädevärttinäluu
hatósugár
radíusgeisli
polomer
polmer
yarı çapyarı çap çizgisi

radius

[ˈreɪdɪəs] N (radiuses, radii (pl)) → radio m
within a radius of 50 milesen un radio de 50 millas

radius

[ˈreɪdiəs] [radii] (pl) n
(gen)rayon m
within a radius of 50 km → dans un rayon de 50 km
(MATHEMATICS)rayon m
(ANATOMY)radius m

radius

n pl <radii>
(Math) → Radius m, → Halbmesser m; (of ship, aircraft)Aktionsradius m, → Wirkungsbereich m; within a 6 km radius (of Hamburg)in einem Umkreis von 6 km (von Hamburg)
(Anat) → Speiche f

radius

[ˈreɪdɪəs] n (radii (pl)) [ˈreɪdɪaɪ] (Math) (fig) → raggio (Anat) → radio
within a radius of 50 miles → in un raggio di 50 miglia

radius

(ˈreidiəs) noun
1. (plural ˈradiuses) the area within a given distance from a central point. They searched within a radius of one mile from the school.
2. (plural ˈradii (-diai) ) a straight line from the centre of a circle to its circumference.

ra·di·us

n. radio.
1. hueso largo del antebrazo;
2. línea recta que une el centro y cualquier punto de la circunferencia.

radius

n (pl radii) radio
References in classic literature ?
We can't charge more than sixpence a mile after the first, within the four-mile radius.
There is in fact a sort of harmony discoverable between the capabilities of the landscape within a circle of ten miles' radius, or the limits of an afternoon walk, and the threescore years and ten of human life.
The theoretic effective radius of this rifle is three hundred miles, but the best they can do in actual service when equipped with their wireless finders and sighters is but a trifle over two hundred miles.
He was acquainted with nearly every principal Arab within a radius of several hundred miles.
It was then very dark, and the scattered lamps made the darkness greater when we were once outside their individual radius.
In some parts, slight curls of smoke emitted a sulphurous smell, proving that the internal fires had lost nothing of their expansive powers, though, having climbed a high acclivity, I could see no volcano for a radius of several miles.
If on Friday night you had taken a pair of compasses and drawn a circle with a radius of five miles round the Woking sand pits, I doubt if you would have had one human being outside it, unless it were some relation of Stent or of the three or four cyclists or London people lying dead on the common, whose emotions or habits were at all affected by the new-comers.
The deer and the pig and the nilghai were milling round and round in a circle of eight or ten miles radius, while the Eaters of Flesh skirmished round its edge.
Then silence brooded over all--silence so complete that it seemed in itself a sentient thing--silence which seemed like incarnate darkness, and conveyed the same idea to all who came within its radius.
For that matter, Reading, and possibly other large towns, were within that radius, so the place might not be so secluded, after all.
Within a radius of five miles there are, as you see, only a very few scattered dwellings.
I have also examined every stable and out-house in Tavistock, and for a radius of ten miles.