critical point

[ krit-i-kuhl point ]

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.

critical point

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

critical point

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.

Word History and Origins

Origin of critical point¹

First recorded in 1875–80

Example Sentences

But the critical point is this: Money is the part we could fix.

From The Daily Beast

Should we be optimistic or pessimistic at this critical point?

From The Daily Beast

But Serry said events had reached a critical point in the West Bank and cautioned that a collapse would leave Israel accountable.

From The Daily Beast

The negative, even dismissive, talk about the Obama White House has reached a critical point.

From The Daily Beast

When this happens at a critical point the ice effectively destroys the power of the wings to provide lift.

From The Daily Beast

At this critical point a man with a horse and buggy turned the corner and started south.

From Project Gutenberg

The race had now reached its critical point and all of the cadets on the hill waited for the outcome with keen interest.

From Project Gutenberg

Affairs had reached this critical point, when a sudden and loud shout was heard down the river.

From Project Gutenberg

To be left in darkness with a plate at its most critical point of development is, to say the least, a great annoyance.

From Project Gutenberg

Besides, the ridge is the critical point when you're crossing on a falling tide, and you want to know when you're past it.'

From Project Gutenberg

Related Words

• turning point