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

However, this new research showed that these point sources, including pulsars, would be extremely faint, and that is good news for scientists who favor annihilating dark matter as the cause of these gamma rays. —Robert Lea, Space.com, 21 June 2026

By detecting these gamma rays, astronomers can trace the lingering remnants of ancient supernovae long after the original stars have vanished. —Sam MacDonald, Scientific American, 19 June 2026

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

Runaway Avalanches In 1994, a satellite searching for extreme deep-space explosions happened to pick up flashes of gamma rays coming from thunderclouds, often alongside lightning. —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