reactor

noun

re·​ac·​tor rē-ˈak-tər How to pronounce reactor (audio)
1
: one that reacts
2
: a device (such as a coil, winding, or conductor of small resistance) used to introduce reactance into an alternating-current circuit
3
a
: a vat for an industrial chemical reaction
b
: a device for the controlled release of nuclear energy (as for producing heat)

Example Sentences

Recent Examples on the Web The Diablo Canyon plant is currently scheduled to shut down in two phases, with the first reactor going offline in 2024 and the second in 2025. Sammy Rothstaff Writer, Los Angeles Times, 21 Nov. 2022 The staff ultimately shut down the last remaining reactor. Joe Parkinson, WSJ, 18 Nov. 2022 One theory is that the fusion reactor within him was produced by the traumas of his youth. David Brooks, The Atlantic, 31 Oct. 2022 Fast-sodium reactors use molten sodium instead of water to cool the reactor and transfer heat, which is safer and more efficient. Tim Fitzpatrick, The Salt Lake Tribune, 27 Oct. 2022 Another 15% is turned into a synthetic natural gas to heat the process, while the remainder — paper, metals, dyes, inks and colorants — exit the reactor as a byproduct, or carbon char, DeBenedictis said. Jennifer Mcdermott, ajc, 21 Oct. 2022 Another 15% is turned into a synthetic natural gas to heat the process, while the remainder — paper, metals, dyes, inks and colorants — exit the reactor as a byproduct, or carbon char, DeBenedictis said. Jennifer Mcdermott, Fortune, 21 Oct. 2022 Another 15% is turned into a synthetic natural gas to heat the process, while the remainder — paper, metals, dyes, inks and colorants — exit the reactor as a byproduct, or carbon char, DeBenedictis said. Jennifer Mcdermott, Anchorage Daily News, 21 Oct. 2022 Denying the severity of the incident, officials didn’t evacuate Pripyat until 36 hours after the reactor exploded—exposing citizens to dangerous levels of radiation. WIRED, 18 Sep. 2022 See More

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

Word History

First Known Use

1890, in the meaning defined at sense 1

Time Traveler
The first known use of reactor was in 1890

Dictionary Entries Near reactor

Cite this Entry

“Reactor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactor. Accessed 8 Dec. 2022.

Kids Definition

reactor

noun
re·​ac·​tor rē-ˈak-tər How to pronounce reactor (audio)
1
: one that reacts
2
: a device for the controlled release of nuclear energy (as for producing heat)

Medical Definition

reactor

noun
re·​ac·​tor rē-ˈak-tər How to pronounce reactor (audio)
1
: one that reacts: as
a
: a chemical reagent
b
: an individual reacting to a stimulus
c
: an individual reacting positively to a foreign substance (as in a test for disease)
reactors to tuberculin
2
a
: a piece of equipment in which a chemical reaction and especially an industrial chemical reaction is carried out
b
: a device for the controlled release of nuclear energy (as for producing heat)

More from Merriam-Webster on reactor

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