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)

Examples of reactor in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
According to the university, reactor manufacturers had been struggling to find sites to build clusters of the small-scale fission facilities. Thomas G. Moukawsher, Newsweek, 6 Feb. 2025 No injuries or adverse health effects resulted from a 1979 accidental release of radioactive gas caused by a cooling failure that led to the meltdown of one of the Three Mile Island reactors, according to the World Nuclear Association. Gary Collins, Baltimore Sun, 2 Feb. 2025 The latest injection of funds will be directed towards manufacturing components in-house, including capacitors for energy storage and magnetic coils for its prototype fusion reactor. New Atlas, 29 Jan. 2025 Steinberg said Blue and legislators spoke generally about the potential of additional nuclear capacity through small modular reactors. Mark Pazniokas, Hartford Courant, 13 Jan. 2025 See all Example Sentences for reactor 

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 20 Feb. 2025.

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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