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

Dangerously high radiation levels make removing melted fuel and other debris from the plant hit by a huge tsunami in 2011 the most daunting challenge in the decades-long decommissioning project.

From Barron's

It acts as a protective barrier, shielding us from harmful cosmic radiation and charged particles streaming from the Sun.

From Science Daily

They found that pieces of amino acids from E. coli bacteria, if trapped in Martian permafrost or ice caps, could survive more than 50 million years even under constant cosmic radiation.

From Science Daily

They do not involve injections, radiation exposure, or demanding tasks for patients.

From Science Daily

Then her eyesight deteriorated, which necessitated a month of radiation.

From Los Angeles Times

Related Words

• emission