Definitions for radiusˈreɪ di əs; -diˌaɪ

This page provides all possible meanings and translations of the word radius

Random House Webster's College Dictionary

ra•di•usˈreɪ di əs; -diˌaɪ(n.)(pl.)-di•i; -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.

    Category: Math

  2. the length of such a line.

    Category: Math

  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.

    Category: Math

  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.

    Category: Anatomy

  8. a corresponding bone in the forelimb of other vertebrates.

    Category: Zoology

Origin of radius:

1590–1600; < L: staff, rod, spoke, beam, ray1

Princeton's WordNet

  1. radius, r(noun)

    the length of a line segment between the center and circumference of a circle or sphere

  2. radius(noun)

    a straight line from the center to the perimeter of a circle (or from the center to the surface of a sphere)

  3. radius(noun)

    a circular region whose area is indicated by the length of its radius

    "they located it within a radius of 2 miles"

  4. radius(noun)

    the outer and slightly shorter of the two bones of the human forearm

  5. spoke, wheel spoke, radius(noun)

    support consisting of a radial member of a wheel joining the hub to the rim

Kernerman English Learner's Dictionary

  1. radius(noun)ˈreɪ di əs

    the distance from the center of a circle to the edge

    Measure the radius.

  2. radiusˈreɪ di əs

    5 miles/10 miles/20km in any direction from a particular point

    the evacuation of everyone within a 3-mile radius


  1. radius(Noun)

    The long bone in the forearm, on the side of the thumb.

  2. radius(Noun)

    The lighter bone (or fused portion of bone) in the forelimb of an animal.

  3. radius(Noun)

    A line segment between any point on the circumference of a circle and its center/centre.

  4. radius(Noun)

    The length of this line segment.

  5. Origin: From radius

Webster Dictionary

  1. Radius(noun)

    a right line drawn or extending from the center of a circle to the periphery; the semidiameter of a circle or sphere

  2. Radius(noun)

    the preaxial bone of the forearm, or brachium, corresponding to the tibia of the hind limb. See Illust. of Artiodactyla

  3. Radius(noun)

    a ray, or outer floret, of the capitulum of such plants as the sunflower and the daisy. See Ray, 2

  4. Radius(noun)

    the barbs of a perfect feather

  5. Radius(noun)

    radiating organs, or color-markings, of the radiates

  6. Radius(noun)

    the movable limb of a sextant or other angular instrument



    Remote Authentication Dial In User Service is a networking protocol that provides centralized Authentication, Authorization, and Accounting management for computers that connect and use a network service. RADIUS was developed by Livingston Enterprises, Inc. in 1991 as an access server authentication and accounting protocol and later brought into the Internet Engineering Task Force standards. Because of the broad support and the ubiquitous nature of the RADIUS protocol, it is often used by ISPs and enterprises to manage access to the Internet or internal networks, wireless networks, and integrated e-mail services. These networks may incorporate modems, DSL, access points, VPNs, network ports, web servers, etc. RADIUS is a client/server protocol that runs in the application layer, using UDP as transport. The Remote Access Server, the Virtual Private Network server, the Network switch with port-based authentication, and the Network Access Server, are all gateways that control access to the network, and all have a RADIUS client component that communicates with the RADIUS server. The RADIUS server is usually a background process running on a UNIX or Microsoft Windows server. RADIUS serves three functions:

Anagrams of radius

  1. Darius

Translations for radius

Kernerman English Multilingual Dictionary


(pluralˈradiuses ) the area within a given distance from a central point

They searched within a radius of one mile from the school.

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