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

“We are at a critical point where our system of healthcare is precariously on the edge,” said Black, a Democrat who represents the town of Essex.

From The Wall Street Journal • Jun. 16, 2026

At Monday's announcement in Ottawa, Carney said that Canada was at a critical point in its history due to its changing relationship with the US, requiring it to invest and build at an urgent pace.

From BBC • Apr. 27, 2026

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

From Barron's • Mar. 11, 2026

But this misses a critical point: The Epstein file dump is not simply playing out as a backdrop against which other acts of American lawlessness are occurring.

From Slate • Feb. 12, 2026

The outpost fell quickly into Octavian’s hands, breaking Mark Antony’s chain at a critical point and disrupting his communication and supply route.

From "Sterling Biographies®: Cleopatra: Egypt's Last and Greatest Queen" by Susan Blackaby

Related Words

• turning point