subcritical

adjective

sub·​crit·​i·​cal ˌsəb-ˈkri-ti-kəl How to pronounce subcritical (audio)
1
: less or lower than critical in respect to a specified factor
2
a
: of insufficient size to sustain a chain reaction
a subcritical mass of fissionable material
b
: designed for use with fissionable material of subcritical mass
a subcritical reactor

Examples of subcritical 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.
One positive is that the process would be subcritical. — New Atlas, 2 Sep. 2025 Fortunately, the installation was in a subcritical state at the time, which greatly decreased the risk of radiation escaping. — IEEE Spectrum, 9 Mar. 2022 The laboratories were thus limited to subcritical experiments, which would not generate a sustained nuclear reaction. — Siegfried Hecker, Foreign Affairs, 26 Nov. 2025 The idea of producing a nuclear explosion by bringing together two subcritical masses of uranium had already been proposed outside the USSR. — Literary Hub, 23 Oct. 2025 See All Example Sentences for subcritical

Word History

First Known Use

1823, in the meaning defined at sense 1

Time Traveler
The first known use of subcritical was in 1823

Rhymes for subcritical

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Browse Nearby Words

subcrescentic
subcritical
subcrossing
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Cite this Entry

“Subcritical.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/subcritical. Accessed 10 Jul. 2026.

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