beta particle


: a high-speed electron
specifically : one emitted by a radioactive nucleus in beta decay

Example Sentences

Recent Examples on the Web The scientific reality is tritium emits an incredibly weak beta particle that is easily stopped by our dead skin layer. James Conca, Forbes, 12 Apr. 2021 The fourth decay can occur by two different routes, with each path releasing one alpha particle and one beta particle before reaching lead-209. Jacqueline Detwiler, Popular Mechanics, 1 Feb. 2020 Of course the frisker was measuring gamma waves in addition to alpha and beta particles; all these people presumably cared about was the particles, which could continue to do harm after being removed from the zone. Aaron Gilbreath, Longreads, 10 Apr. 2018 Radionuclides: Water systems monitor for beta particles and photon radioactivity in drinking water. Nathaniel Levine, sacbee, 22 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'beta particle.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1904, in the meaning defined above

Time Traveler
The first known use of beta particle was in 1904

Dictionary Entries Near beta particle

Cite this Entry

“Beta particle.” Dictionary, Merriam-Webster, Accessed 20 Mar. 2023.

Kids Definition

beta particle

: an electron or positron that is thrown out from the nucleus of an atom during radioactive decay
also : a high-speed electron or positron

Medical Definition

beta particle

: a high-speed electron
specifically : one emitted during radioactive decay of an atomic nucleus

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