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.
- (of a function of a single variable) a point at which the derivative of the function is zero.
- (of a function of several variables) a point at which all partial derivatives of the function are zero.
Moot Point vs. Mute PointYou may have heard coworkers or acquaintances refer to an inconsequential or irrelevant point as a moot point, or maybe you’ve heard mute point instead. Fans of the TV show Friends may have heard a third variation: moo point (because, according to Joey, a cow’s opinion doesn’t matter). But which expression is correct, and what exactly does it mean? The correct phrase is moot point. …
Origin of critical point
First recorded in 1875–80
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for critical point
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Science definitions for critical point
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. Compare triple point.
- A maximum, minimum, or point of inflection of a curve.
- A point at which the derivative of a function is zero, infinite, or undefined.
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