radiation

[rey-dee-ey-shuhn]

noun

1. Physics.

   1. the process in which energy is emitted as particles or waves.

   2. the complete process in which energy is emitted by one body, transmitted through an intervening medium or space, and absorbed by another body.

   3. the energy transferred by these processes.

2. the act or process of radiating.

3. something that is radiated.

4. radial arrangement of parts.

radiation

/ ˌreɪdɪˈeɪʃən /

noun

1. physics

   1. the emission or transfer of radiant energy as particles, electromagnetic waves, sound, etc

   2. the particles, etc, emitted, esp the particles and gamma rays emitted in nuclear decay

2. Also called: radiation therapy. med treatment using a radioactive substance

3. anatomy a group of nerve fibres that diverge from their common source

4. See adaptive radiation

5. the act, state, or process of radiating or being radiated

6. surveying the fixing of points around a central plane table by using an alidade and measuring tape

radiation

1. 1. Streams of photons, electrons, small nuclei, or other particles. Radiation is given off by a wide variety of processes, such as thermal activity, nuclear reactions (as in fission), and by radioactive decay.

   2. The emission or movement of such particles through space or a medium, such as air.

2. The use of such energy, especially x-rays, in medical diagnosis and treatment.

radiation

1. Energy sent out in the form of particles or waves. (See alpha radiation, beta radiation, blackbody, cosmic rays, electromagnetic radiation, fluorescence, gamma radiation, photon, and quanta.)

Other Word Forms

• radiational adjective
• antiradiation adjective
• interradiation noun
• nonradiation noun

Word History and Origins

Origin of radiation¹

First recorded in 1545–55; from Latin radiātiōn-, stem of radiātiō “beam, gleam, shine”; equivalent to radiate + -ion

Example Sentences

Her apartment is equipped with radiation detectors, air-quality monitors and emergency lights.

Read more on Wall Street Journal

She added that Sanders would not need radiation or chemotherapy treatments.

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In this process, magnetic field lines break and reassemble, leading to magnetic energy being converted into heat, radiation, and eruptions of plasma.

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He was soon diagnosed with acute lymphocytic leukemia and underwent chemotherapy and radiation.

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It is not yet clear how much damage was done to the facilities, though the UN's nuclear watchdog says there had been "no increase" in off-site radiation levels reported.

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Related Words

• emission