temperature

[ tem-per-uh-cher, -choor, -pruh-, -per-cher ]

noun

1. a measure of the warmth or coldness of an object or substance with reference to some standard value. The temperature of two systems is the same when the systems are in thermal equilibrium. : T
2. Physiology, Pathology.
   1. the degree of heat in a living body, normally about 98.6°F (37°C) in humans.
   2. the excess of this above the normal.
3. Obsolete. mildness, as of the weather.
4. Obsolete. temperament.

temperature

/ ˈtɛmprɪtʃə /

noun

1. the degree of hotness of a body, substance, or medium; a physical property related to the average kinetic energy of the atoms or molecules of a substance
2. a measure of this degree of hotness, indicated on a scale that has one or more fixed reference points
3. informal.
   a body temperature in excess of the normal
4. archaic.
   1. compromise
   2. temperament
   3. temperance

temperature

/ tĕm′pər-ə-chr′ /

1. A measure of the ability of a substance, or more generally of any physical system, to transfer heat energy to another physical system. The temperature of a substance is closely related to the average kinetic energy of its molecules.
2. See also Boyle's law
3. Any of various standardized numerical measures of this ability, such as the Kelvin, Fahrenheit, and Celsius scales.
4. An abnormally high body temperature; a fever.

Word History and Origins

Origin of temperature¹

First recorded in 1525–35, temperature is from the Latin word temperātūra a tempering. See temperate, -ure

Word History and Origins

Origin of temperature¹

C16 (originally: a mingling): from Latin temperātūra proportion, from temperāre to temper

Usage

Heat and temperature are closely related but distinct and sometimes subtle ideas. Heat is simply transferred thermal energy—most commonly, the kinetic energy of molecules making up substance, vibrating and bouncing against each other. A substance's temperature, on the other hand, is a measure of its ability to transfer heat, rather than the amount of heat transferred. For example, a match lit under a pot of boiling water reaches a much higher temperature than the water, but it is able to give off much less heat, since only a small amount of thermal energy is created and released by it. When any two substances of different temperatures are in thermal contact, the laws of thermodynamics state that heat flows from the higher-temperature substance into the lower-temperature substance, raising the temperature of the heated body and lowering the temperature of the body releasing heat until thermal equilibrium is reached, and the temperatures are the same. Thus temperature describes a characteristic of matter that determines the direction and extent of heat transfer, so the match with little heat but high temperature still adds energy to the water when placed under the pot. Providing a closed physical system with heat generally raises its temperature but not necessarily; for example, ice at zero degrees Celsius requires considerable additional heat in order to melt into water at zero degrees Celsius. Temperature can be related to the average kinetic energy of the molecules of gases, though this relation breaks down in most real cases involving liquids, solids, substances with larger molecules, and radiation with no mass, such as light. The two most common temperature scales, Celsius (C) and Fahrenheit (F), are based on the freezing and boiling points of water. On the Celsius scale there are 100 increments between the two points, and on the Fahrenheit scale there are 180. Scientists also use the International System units called Kelvins (K). A difference in temperature of one degree is equivalent in the Celsius and Kelvin scales, but their absolute scales are different: while zero degrees C is the temperature at which water freezes (at a pressure of one atmosphere), zero degrees K (−273.72 degrees C), also called absolute zero, is the least possible temperature for a system, representing a theoretical state from which no heat can be extracted.

Idioms and Phrases

see run a fever (temperature) .

Example Sentences

The configuration with the best results allowed the TCM reactor to heat the air exiting the building, which is at the same temperature and humidity as the indoor air.

From Science Daily

Martinez, whose nonprofit We Are Not Invisible raises funds for homeless needs, put out a late-night plea on Facebook as the temperature dropped below 50.

From Los Angeles Times

It was introduced in 1997 as a universal payment to reassure pensioners they would be able to heat their homes as temperatures drop, although in practice recipients can spend it on whatever they want.

From BBC

However, with temperatures dropping to freezing levels and snow hitting parts of the UK, rising energy bills will once again become the focus of many households.

From BBC

Cold temperatures have essentially the opposite effect, slowing metabolism and movement of herbicides within the plant and rendering them less effective.

From Science Daily

Related Words

• climate
• cold
• condition
• heat
• warmth