subcritical

American  

[suhb-krit-i-kuhl] / sʌbˈkrɪt ɪ kəl /

adjective

1. Physics. pertaining to a state, value, or quantity that is less than critical, especially to a mass of radioactive material.

2. being of less than critical importance.

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subcritical British  

/ sʌbˈkrɪtɪkəl /

adjective

1. physics (of a nuclear reaction, power station, etc) having or involving a chain reaction that is not self-sustaining; not yet critical

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Etymology

Origin of subcritical

First recorded in 1940–45; sub- + critical

Example Sentences

See Examples For:

subcritical

The U.S. has been modernizing its warheads with subcritical testing that produces zero nuclear yield.

From The Wall Street Journal ● Nov. 17, 2025

"Other tests, both subcritical, or those without a chain nuclear reaction, and carrier tests, have never been prohibited," Lavrov added.

From Barron's ● Nov. 11, 2025

National Nuclear Security Administration, which oversees the U.S. nuclear arsenal, announced in June that the United States is open to having international observers monitor the subcritical experiments.

From Reuters ● Oct. 10, 2023

Scorpius will be fully assembled in an underground complex at the facility formerly known as the Nevada Test Site, where scientists have been conducting subcritical experiments since 1995 and nuclear testing dates to 1951.

From Washington Times ● Oct. 5, 2023

I suppose it would blow one subcritical mass into another.

From The Cosmic Computer by H. Beam Piper