radiation

American  

[rey-dee-ey-shuhn] / ˌreɪ diˈeɪ ʃən /

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.

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radiation British  

/ 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

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radiation Scientific  

/ rā′dē-ā′shən /

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.

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radiation Cultural  

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.)

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Other Word Forms

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

Etymology

Origin of radiation

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

Example Sentences

The amount of radiation used is small, akin to a mammogram, and the scans typically don’t need to be repeated.

From The Wall Street Journal

With the peak in the solar cycle, they will also be keeping an eye on solar activity and enhanced radiation which could affect the astronauts.

From BBC

Powerful radiation from active supermassive black holes, which are believed to sit at the center of most galaxies, can do more than shape their own surroundings.

From Science Daily

They'll have to work out how to generate power and build habitats to protect people from extreme temperatures as well as dangerous space radiation.

From BBC

Arno Penzias at Bell Labs won the Nobel Prize in Physics for discovering “cosmic microwave background radiation” from the Big Bang.

From The Wall Street Journal

Related Words

• emission