gamma ray

noun

: a photon emitted spontaneously by a radioactive substance
also : a photon of higher energy than that of an X-ray

Examples of gamma ray in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
That’s because almost everything cosmologists know about the universe comes from observations of electromagnetic radiation in the form of visible light, as well as wavelengths that run the gamut --- from the far infrared to the highest energy gamma rays. Bruce Dorminey, Forbes.com, 23 Apr. 2025 Previous research also indicated that Earth looks down the axis of this system, known as Wolf-Rayet 104, raising concerns that our planet could be hit by intense gamma rays released from the stars' eventual explosive deaths. Sharmila Kuthunur, Space.com, 21 Mar. 2025 Long-duration GRBs, which are blasts of high-energy gamma rays that last over two seconds, come from the core collapse of massive stars that leads to a supernova explosion. Robert Lea, Space.com, 20 Apr. 2025 When the records were examined, it was found that the detectors had been triggered by occasional bursts of gamma rays, but that the source could not possibly be anything near Earth. Mark Fischetti, Scientific American, 17 Mar. 2025 See All Example Sentences for gamma ray

Word History

First Known Use

1903, in the meaning defined above

Time Traveler
The first known use of gamma ray was in 1903

Cite this Entry

“Gamma ray.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/gamma%20ray. Accessed 18 May. 2025.

Kids Definition

gamma ray

noun
: a ray that is like an X-ray but of higher energy and that is given off especially by a radioactive substance

Medical Definition

gamma ray

noun
: a photon emitted spontaneously by a radioactive substance
also : a high-energy photon
usually used in plural

More from Merriam-Webster on gamma ray

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