annihilation radiation

noun

: radiation produced by the mutually annihilating coalescence of a particle and its antiparticle from which two radiation quanta travel in opposite directions with a wavelength corresponding to that of very short gamma rays, being approximately 0.024 angstrom

Word History

First Known Use

1935, in the meaning defined above

Time Traveler
The first known use of annihilation radiation was in 1935

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Dictionary Entries Near annihilation radiation

annihilationist

annihilation radiation

annihilative

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Cite this Entry

“Annihilation radiation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/annihilation%20radiation. Accessed 27 Nov. 2024.

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