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

After wrapping on “Days” in June, Rogers began daily radiation and chemotherapy treatments.

Read more on Los Angeles Times

Recent studies also suggest that this movement influences Earth's radiation belts, which are regions filled with fast-moving, high-energy particles.

Read more on Science Daily

If Russia were to launch a Burevestnik, it could become a target before getting airborne because its nuclear reactor would emit radiation detectable from great distances, including from space.

Read more on The Wall Street Journal

It is unclear what isotope of uranium the men are alleged to have sought - though all can emit harmful radiation - and their intended purpose for it.

Read more on BBC

"We can at least treat 50 patients per day for chemotherapy and radiation and even more than that. Other hospitals can do a lot of surgeries," the doctor tells me.

Read more on BBC

Related Words

• emission