Definition

1. Noun:
   • Energy emitted as particles or waves: The process by which energy is emitted from a source and travels through space or a material medium. This includes electromagnetic waves (like light, X-rays) and particle streams (like alpha and beta particles).
   • The act of spreading out from a central point: The process of spreading outward from a central source.
   • A radial arrangement: Something arranged in lines extending from a common center.
   • Medical treatment: The treatment of disease, especially cancer, using controlled exposure to radioactive substances or high-energy rays.
   • Illness from exposure: The harmful syndrome resulting from excessive exposure to ionizing radiation.

Examples of Usage

• Noun:
  • The sun emits heat and light radiation.
  • The radiation from the antenna spreads in all directions.
  • The patient underwent radiation to shrink the tumor.
  • After the accident, several workers showed symptoms of acute radiation.

Advanced Usage

• "Background radiation": The low-level ionizing radiation constantly present in the environment from natural and artificial sources.
  • Geiger counters can measure background radiation.
• "Thermal radiation": Electromagnetic radiation generated by the thermal motion of particles in matter.
  • You can feel the thermal radiation from a hot stove.

Variants and Related Words

• Radiate (verb): To emit energy, especially light or heat, in the form of rays or waves. Also, to spread out from a center.
  • The heater radiated warmth.
• Radiant (adjective): Sending out light; shining brightly. Also, showing great joy, love, or health.
  • She had a radiant smile.
• Radioactivity (noun): The property of some unstable atomic nuclei to spontaneously emit radiation.
  • The radioactivity of the material decreases over time.

Synonyms

• Emission: The production and discharge of something, especially gas or radiation.
• Irradiation: The process of exposing someone or something to radiation.

Related Phrases

• Radiation therapy: The medical use of ionizing radiation to treat cancer.
  • Radiation therapy is often used in combination with surgery.
• Radiation sickness: An illness caused by excessive exposure to ionizing radiation.
  • The early symptoms of radiation sickness include nausea and fatigue.

Related Idioms

• To radiate confidence/joy: To show a lot of a positive quality very clearly.
  • The speaker radiated confidence during the presentation.

Noun

1. (medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance
2. a radial arrangement of nerve fibers connecting different parts of the brain
3. the spread of a group of organisms into new habitats
4. the spontaneous emission of a stream of particles or electromagnetic rays in nuclear decay
5. syndrome resulting from exposure to ionizing radiation (e.g., exposure to radioactive chemicals or to nuclear explosions); low doses cause diarrhea and nausea and vomiting and sometimes loss of hair; greater exposure can cause sterility and cataracts and some forms of cancer and other diseases; severe exposure can cause death within hours
   • he was suffering from radiation
6. the act of spreading outward from a central source
7. energy that is radiated or transmitted in the form of rays or waves or particles