supercritical

American  

[soo-per-krit-i-kuhl] / ˌsu pərˈkrɪt ɪ kəl /

adjective

1. extremely critical.

2. Physics. pertaining to a mass of radioactive material in which the rate of a chain reaction increases with time.

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supercritical British  

/ ˌsuːpəˈkrɪtɪkəl /

adjective

1. physics (of a fluid) brought to a temperature and pressure higher than its critical temperature and pressure, so that its physical and chemical properties change

2. nuclear physics of or containing more than the critical mass

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Other Word Forms

• supercritically adverb
• supercriticalness noun

Etymology

Origin of supercritical

First recorded in 1600–10; super- + critical

Example Sentences

In this model, cracked regions of the crust are thought to contain water at extremely high temperatures and pressures, possibly in a supercritical state.

From Science Daily • Feb. 24, 2026

But in December, the government said it would keep Cirebon-1 open, citing its long potential lifespan and "supercritical" technology, which burns coal more efficiently than older plants.

From Barron's • Feb. 18, 2026

It relies on heating and pressurising water to such a high degree that it enters a new state of matter: a so-called supercritical state.

From BBC • Aug. 18, 2025

Other suggested techniques, such as supercritical water oxidation or plasma reactors, have the same drawbacks.

From Salon • Apr. 17, 2024

Fr. origin, surface, surfeit, surpass, surprise;—Eng. compounds, superabundant, supercargo, supercritical.

From Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements) by Various