from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A form of energy associated with the motion of atoms or molecules and capable of being transmitted through solid and fluid media by conduction, through fluid media by convection, and through empty space by radiation.
  • noun The transfer of energy from one body to another as a result of a difference in temperature or a change in phase.
  • noun The sensation or perception of such energy as warmth or hotness.
  • noun An abnormally high bodily temperature, as from a fever.
  • noun The condition of being hot.
  • noun A degree of warmth or hotness.
  • noun The warming of a room or building by a furnace or another source of energy.
  • noun A furnace or other source of warmth in a room or building.
  • noun A hot season; a spell of hot weather.
  • noun Intensity, as of passion, emotion, color, appearance, or effect.
  • noun The most intense or active stage.
  • noun A burning sensation in the mouth produced by spicy flavoring in food.
  • noun Estrus.
  • noun One of a series of efforts or attempts.
  • noun Sports & Games One round of several in a competition, such as a race.
  • noun A preliminary contest held to determine finalists.
  • noun Informal Pressure; stress.
  • noun An intensification of police activity in pursuing criminals.
  • noun The police. Used with the.
  • noun Slang Adverse comments or hostile criticism.
  • noun Slang A firearm, especially a pistol.
  • intransitive verb To make warm or hot.
  • intransitive verb To excite the feelings of; inflame.
  • intransitive verb Physics To increase the molecular or kinetic energy of (an object).
  • intransitive verb To become warm or hot.
  • intransitive verb To become excited emotionally or intellectually.

from The Century Dictionary.

  • noun The quantity or weight of metal undergoing a metallurgical process. See heat. 4.
  • noun In electricity, that portion of the heat developed in an electric circuit which cannot be converted directly into electrie energy. The total heat in an electric circuit is HJ= IRt + PIt, where H is the heat in calories, J is the mechanical equivalent, I the current, R the resistance, t the time during which the current flows, and P is the difference of potential due to the heating of any metal junctions that may exist in the circuit. The term IRt represents the irreversible heat. Also called ohmic heat. Compare reversible heat.
  • noun The heat in calories required to convert a gram of liquid at its melting-point into saturated vapor at a given pressure.
  • To cause to grow warm; communicate heat to; make hot: as, to heat an oven or a furnace; to heat iron. See heat, n., 2.
  • To make feverish; stimulate; excite: as, to heat the blood.
  • To warm with emotion, passion, or desire; rouse into action; animate; encourage.
  • To run a heat over, as in a race.
  • To grow warm or hot; come to a heated condition, from the effect either of something external or of chemical action, as in fermentation or decomposition.
  • noun A sensation of the kind produced by close proximity to fire.
  • noun That condition of a material body which is capable of producing the sensation of heat; in physics, the corresponding specific form of energy, consisting in an agitation of the molecules of matter, and measured by the total kinetic energy of such agitation. See energy, 7.
  • noun In ordinary use, a sensibly high temperature, as the warmth of the sun, or of the body.
  • noun A heating, as of a piece of iron to be wrought by a blacksmith, or of a mass of metal to be melted in a furnace; an exposure to intense heat.
  • noun Hence Violent action; high activity; intense and uninterrupted effort: as, to do a thing at a heat.
  • noun Especially— A single course in a horse-race or other contest.
  • noun A division of a race or contest when the contestants are too numerous to run at once, the race being finally decided by the winners (or winners and seconds) of each division running a final race or heat.
  • noun Indication of high temperature, as the condition or color of the body or part of the body; redness; high color.; flush.
  • noun Vehemence; rage; violence; excitement; animation; fervency; ardor; zeal: as, the heat of battle or of argument; the heat of passion or of eloquence.


from The American Heritage® Dictionary of the English Language, 4th Edition

[Middle English hete, from Old English hǣtu; see kai- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

Old English hætan

from Wiktionary, Creative Commons Attribution/Share-Alike License

Old English hæte.


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  • Some say Cheney 'feeling the heat' over potential probes/Kentucky election officials nabbed in touch-screen vote scam yahooBuzzArticleHeadline = 'Some say Cheney \'feeling the heat\' over potential probes/Kentucky election officials nabbed in touch-screen vote scam '; yahooBuzzArticleSummary =' Article: Several observers suspect that Cheney is nervous about calls for investigations into the Bush administration and is going on the offensive in his latest attacks on President Obama.

    Some say Cheney 'feeling the heat' over potential probes / Kentucky election officials nabbed in touch-screen vote scam 2009

  • Believe it or not, water vapor and other minor GHG are transferors of heat, not accumulators of heat…

    Unthreaded #21 « Climate Audit 2007

  • Internal heat gains, in the form of heat output from human bodies, equipment, cooking and lighting (often referred to as “wild heat”), can present quite a problem and should be minimized in hot seasons.

    3. Design rules 1993

  • The heat absorbed during ebullition consists of that necessary to dissociate the molecules, or the _inner latent heat_, and that necessary to overcome the resistance to the increase in volume, or the _outer latent heat_.

    Steam, Its Generation and Use

  • If the source of heat be withdrawn from the steam pipes, the temperature will soon fall below 212° and the steam immediately in contact with the pipes will condense: but in condensing, the steam parts with its _latent heat_ and this heat in passing from the latent to the sensible state, will again raise the temperature of pipes.

    Woodward's Graperies and Horticultural Buildings 1867

  • The invisible heat, emitted both by dark bodies and by luminous ones, flies through space with the velosity of light, and is called _radiant heat_.

    Six Lectures on Light Delivered In The United States In 1872-1873 John Tyndall 1856

  • _latent heat of evaporation_ and the sum of this latent heat of evaporation and the heat of the liquid make the _total heat_ of the steam.

    Steam, Its Generation and Use

  • This cause of devaporation has been ingeniously explained by Dr. Hutton in the Transact. of Edinburgh, Vol. I, and seems to arise from this circumstance; the particles of air of the N.E. wind educe part of the heat from the S.W. wind, and therefore the water which was dissolved by that quantity of _heat_ is precipitated; all the other part of the water, which was suspended by its attraction to the particles of air, or dissolved in the remainder of the heat, continues unprecipitated.

    The Botanic Garden A Poem in Two Parts. Part 1: the Economy of Vegetation Erasmus Darwin 1766

  • (heat recovery) for electric power, process needs or space heat­ boiler. ing.

    Recently Uploaded Slideshows 2009

  • Eli Jacks, a meteorologist with the National Weather Service in Silver Spring, Md., said that he had no idea where the term "heat dome" originated, and that while he prefers the term "heat wave," the dome metaphor was "an apt way to describe this huge bubble of hot air."

    NYT > Home Page By ERIK ECKHOLM 2011

  • I don’t want to hide away in my big house watching TV by myself or with other millionaires while people are having to visit food banks or that new phenomenon, heat banks.

    I’m a millionaire – this is why I’m at Davos begging to pay more tax | Phil White Phil White 2023

  • The oppressive heat that settled in the Pacific Northwest was the result of a wide and deep mass of high-pressure air that, because of a wavy jet stream, parked itself over much of the region. Known as a heat dome, such an enormous high-pressure zone acts like a lid, trapping heat so it accumulates.

    Pacific Northwest Continues to Bake Beneath ‘Heat Dome’ By 2021


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