gamma ray

IPA/ˈɡæm.ə ˌreɪ/
IPA/ˈɡæm.ə ˌreɪ/

gamma ray — noun

1. a very powerful ray of energy released when radioactive material breaks down

1.nounC1
Definition

a very powerful ray of energy released when radioactive material breaks down

Example

Scientists used special sensors to detect gamma rays from the dying star.

detect gamma rays from a star

A thick wall helps stop gamma rays from reaching the hospital room.

block gamma rays with shielding

Common collocations
  • detect gamma rays
  • give off gamma rays
  • gamma rays from a star
  • stop gamma rays
Synonyms
  • gamma radiation

    usually names the radiation as a type rather than one individual ray

Grammar Patterns

detect gamma rays

gamma rays from radioactive material

block gamma rays with thick shielding

Usage Note

Usually countable and often used in the plural. This term is common in science, space, and medical writing when people talk about radiation released by stars or radioactive material.

Etymology

GreekEnglish

Scientists named this kind of radiation with gamma, the name of the third letter of the Greek alphabet, as part of a system for classifying different rays. Ray comes from an older word for a line or beam of light, so gamma ray literally means a ray in the gamma class.

First known use

1903

1903, in the meaning defined above