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

At its heart lies a supermassive black hole that draws in matter from nearby space and propels some of it outward in colossal plasma jets filled with radiation, heat, magnetic fields, and heavy particles.

Read more on Science Daily

Earth is lucky to have a magnetic field that shields the planet -- and everything living on it -- from dangerous cosmic radiation.

Read more on Science Daily

This radiation is super powerful, and it comes from an equally powerful source.

Read more on Space Scoop

Because this object gives off no light or detectable radiation, scientists identified it through its gravitational pull on light passing nearby, an effect known as gravitational lensing.

Read more on Science Daily

The university said the pits may be connected to underground cave networks that could provide natural shelter from harmful radiation and micrometeorite impacts, as well as harbour water ice.

Read more on BBC

Related Words

• emission