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

For years, Fermi has detected an unexplained glow of gamma rays coming from the center of the Milky Way. —Christopher Karwin, The Conversation, 8 June 2026

One of the first clues discovered by the researchers was the absence of an electromagnetic radiation signal in radio, optical, X-ray, or gamma rays from the same region of space that the neutrino appeared to have originated from. —Robert Lea, Space.com, 28 May 2026

Even gamma rays get their day in the sun (so to speak), with the Fermi Gamma-Ray Space Telescope and Swift still operating and producing amazing data. —Phil Plait, Scientific American, 15 May 2026

Long needles of ice may set off bolts in one cloud while a deluge of electrons producing gamma rays does it in another cloud. —Quanta Magazine, 6 May 2026

Word History

First Known Use

1903, in the meaning defined above

Rhymes for gamma ray

• aaa
• alleyway
• alumnae
• anime
• anyway
• arete
• attache
• axillae
• baa
• beaujolais
• bouvier
• breakaway

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