critical point

American  

[krit-i-kuhl point] / ˈkrɪt ɪ kəl ˈpɔɪnt /

noun

1. Physics. the point at which a substance in one phase, as the liquid, has the same density, pressure, and temperature as in another phase, as the gaseous.

   The volume of water at the critical point is uniquely determined by the critical temperature.

2. Mathematics.

   1. (of a function of a single variable) a point at which the derivative of the function is zero.

      One critical point, at x = 0, is a decreasing function for positive x.

   2. (of a function of several variables) a point at which all partial derivatives of the function are zero.

      Find and classify all the critical points of the given function.

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critical point British  

noun

1. physics

   1. the point on a phase diagram that represents the critical state of a substance

   2. another name for critical state

2. maths the US name for stationary point

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critical point Scientific  

1. Physics The temperature and pressure at which the liquid and gaseous phases of a pure substance become unstable and fluctuate locally within the substance. The critical point of water is at a temperature of 374°C (705.2°F) and a pressure of 218 atmospheres, at which point it becomes opaque.

2. Physics Compare triple point

3. Mathematics

   1. A maximum, minimum, or point of inflection of a curve.

   2. A point at which the derivative of a function is zero, infinite, or undefined.

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Etymology

Origin of critical point

First recorded in 1875–80

Example Sentences

See Examples For:

critical point

Our forthcoming report from the American Enterprise Institute and the Institute for Family Studies shows how thoroughly Washington has neglected this critical point.

From The Wall Street Journal ● Jul. 24, 2026

Of course, there’s “one critical point for families,” she said.

From MarketWatch ● Jul. 2, 2026

"It looks almost that you cannot escape the critical point if you entered it, almost like a Black Hole," says Robin Tyburski, researcher in Chemical Physics at Stockholm University.

From Science Daily ● Mar. 29, 2026

"This could potentially hamper US warfighters at a critical point in time."

From Barron's ● Mar. 11, 2026

It wasn’t the Sapa Inca who should be in my thoughts at this critical point.

From "The Ugly One" by Leanne Statland Ellis

Related Words

• turning point