heat

American  

[heet] / hit /

noun

• heat
  plural

1. a relatively high degree of warmth.

   Antonyms:

   coolness

2. the condition or quality of being hot.

   The heat of the oven will caramelize the natural sugars in the vegetables, enhancing their flavor.

   Synonyms:

   warmth, hotness

3. the degree of hotness; temperature.

   Heat is measured with a thermometer.

   Moderate heat is sufficient for a child’s bathwater.

   Synonyms:

   caloricity

4. the sensation of warmth or hotness.

   She enjoyed the pleasant heat on her face and hands from the crackling fire.

5. a bodily temperature higher than normal.

   The heat caused by physical exertion is reduced by sweating.

6. added or external energy that causes a rise in temperature, expansion, evaporation, or other physical change.

   The application of heat causes particles of matter to move more rapidly.

7. Physics. a nonmechanical energy transfer with reference to a temperature difference between a system and its surroundings or between two parts of the same system. Q

8. a hot condition of the atmosphere or physical environment; hot season or weather.

   They go up north in the summer to escape the heat.

9. a period of hot weather.

10. a sharp, pungent flavor, as that produced by strong spices.

11. warmth or intensity of feeling; vehemence; passion.

    He spoke with much heat and at great length.

    Synonyms:

    impetuosity, excitement, fever, flush, zeal, fervor, ardor

    Antonyms:

    indifference

12. a point or period of high intensity in an action, process, situation, etc..

    Soldiers must make snap decisions in the heat of battle with no certainty of the outcome.

    In the heat of his hasty departure he forgot his keys.

13. Often the heat pressure to act, work, etc..

    All this media attention is putting the heat on him to change his position on the issue.

    Give me a deadline—I work best under a little heat.

14. Slang. intensified pressure verging on coercion and involving intimidation or implied threat, especially in a police investigation.

    They had to use heat to get the guy to give them some names.

15. Slang. the heat, the police.

    We split when we saw the heat coming.

16. Slang. armed protection, especially a pistol, revolver, or other firearm.

    All guards carry some heat.

17. a single intense effort; a sustained, concentrated, and continuous operation.

    The painting was finished at a heat.

18. Sports.

    1. a single course in or division of a race or other contest.

    2. a race or other contest in which competitors attempt to qualify for entry in the final race or contest.

19. Metallurgy.

    1. a single operation of heating, as of metal in a furnace, in the treating and melting of metals.

    2. a quantity of metal produced by such an operation.

20. Zoology.

    1. sexual receptiveness in animals, especially females.

    2. the period or duration of such receptiveness.

       Do not frequent dog parks or other dog-populated areas while your dog is in heat.

21. Slang. the heat, awesome or excellent; cool.

    Check out the photography on her website—that stuff’s the heat!

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verb (used with object)

• heats,
  present (3rd person singular)
• heated,
  past participle,  past
• heating
  present participle

1. to make hot or warm (often followed byup ).

   Let me heat this leftover soup in the microwave.

   Antonyms:

   cool

2. to excite emotionally; inflame or rouse with passion.

   Synonyms:

   animate, stir, warm, stimulate

verb (used without object)

• heats,
  present (3rd person singular)
• heated,
  past participle,  past
• heating
  present participle

1. to become hot or warm (often followed byup ).

   It takes a while for the house to heat up.

2. to become excited emotionally.

verb phrase

1. heat up to increase or become more active or intense.

   Business competition will heat up toward the end of the year.

heat British  

/ hiːt /

noun

1. 1. the energy transferred as a result of a difference in temperature

   2. the random kinetic energy of the atoms, molecules, or ions in a substance or body

2. the sensation caused in the body by heat energy; warmth

3. the state or quality of being hot

4. hot weather

   the heat of summer

5. intensity of feeling; passion

   the heat of rage

6. pressure

   the political heat on the government over the economy

7. the most intense or active part

   the heat of the battle

8. a period or condition of sexual excitement in female mammals that occurs at oestrus

9. sport

   1. a preliminary eliminating contest in a competition

   2. a single section of a contest

10. slang police activity after a crime

    the heat is off

11. slang criticism or abuse

    he took a lot of heat for that mistake

12. without pausing to think

13. 1. Also: in season. (of some female mammals) sexually receptive

    2. in a state of sexual excitement

14. slang the police

15. informal to increase the intensity of activity, coercion, etc

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verb

1. to make or become hot or warm

2. to make or become excited or intense

heat Scientific  

/ hēt /

1. Internal energy that is transferred to a physical system from outside the system because of a difference in temperature and does not result in work done by the system on its surroundings. Absorption of energy by a system as heat takes the form of increased kinetic energy of its molecules, thus resulting in an increase in temperature of the system. Heat is transferred from one system to another in the direction of higher to lower temperature.

2. See also thermodynamics See Note at temperature

3. See estrus

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heat Cultural  

1. In physics, a form of energy associated with the movement of atoms and molecules in any material. The higher the temperature of a material, the faster the atoms are moving, and hence the greater the amount of energy present as heat. (See infrared radiation.)

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heat Idioms  

More idioms and phrases containing heat

• dead heat
• in heat
• in the heat of the moment
• turn up the heat

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Other Word Forms

Derived Forms

• reheat
  verb
• underheat
  verb (used with object)
• heatable
  adjective
• heatful
  adjective
• heatless
  adjective
• heatlike
  adjective
• reheatable
  adjective
• self-heating
  adjective
• unheatable
  adjective

Inflected Forms

Nouns

• heat
  plural

Participles

• heating
  present
• heated
  past

Conjugated Forms

Present

• heat
  simple
• heats
  simple
• have heated
  perfect
• has heated
  perfect
• am heating
  progressive
• are heating
  progressive
• is heating
  progressive
• have been heating
  perfect progressive
• has been heating
  perfect progressive

Past

• heated
  simple
• had heated
  perfect
• was heating
  progressive
• were heating
  progressive
• had been heating
  perfect progressive

Future

• will heat
  simple
• will have heated
  perfect
• will be heating
  progressive
• will have been heating
  perfect progressive

Etymology

Origin of heat

First recorded before 900; Middle English hete, Old English hǣtu; akin to German Hitze; see hot

Explanation

Objects that give off heat — or a feeling of warmth — include the sun, a radiator, and even your body. You can feel a marked difference in air temperature if you hold your hand near the heat of a candle flame, for example. Heat can also mean the intensity of an emotion. In the heat of an argument, you need to watch what you say, because you may regret it later. The verb heat means to make something hot, like when you heat up last night's pizza to eat for lunch today. When things heat up, they become exciting or intense, the way thrilling chase scenes heat up your favorite action movie.

Example Sentences

See Examples For:

heat heats heated heating

But in times of heat stress, algae can produce toxins, forcing their hosts to expel them.

From Barron's ● Oct. 14, 2026

In the Northeast, diesel also comes out of the same refined-oil pool as the heating oil used to heat homes in the winter, Carpenter said.

From MarketWatch ● Oct. 14, 2026

At that time, Earth and the Moon were much closer together, and gravitational tidal forces generated more heat on the lunar near side than on the far side.

From Science Daily ● Oct. 14, 2026

"For people who are on a very fixed income, it literally is coming down to the point where it is fuel or food, which is awful because you've got to heat your home."

From BBC ● Oct. 14, 2026

My cheeks heat up at the thought of her seeing the dishevelled old woman shuffling up our driveway in her slippers.

From "Code Name Kingfisher" by Liz Kessler

The more dust that gathers on those windows, the less sunlight gets inside, and the slower the greenhouse heats up in the first place.

From BBC ● Sep. 8, 2026

When the Sun is more active, extra energy heats the atmosphere and makes its outer layers extend farther into space.

From Science Daily ● Sep. 1, 2026

Himalayan glaciers, which provide critical water to nearly two billion people, are melting faster as the planet heats, exposing communities to unpredictable, costly disasters.

From Barron's ● Aug. 29, 2026

That’s because ocean water expands as it heats.

From Los Angeles Times ● Aug. 24, 2026

At Putney he slipped his boat into the water, leaned deep into his oars, and over the course of three heats defeated a field of fifty- eight oarsmen.

From "The Boys in the Boat: Nine Americans and Their Epic Quest for Gold at the 1936 Berlin Olympics" by Daniel James Brown

Intermarché said its fridges had heated up to 50C for six hours overnight into Monday, and the retailer had thrown away all the affected food to avoid health risks, the Reuters news agency reported.

From BBC ● Oct. 12, 2026

Leaders quickly shelved the proposal after debate turned heated.

From The Wall Street Journal ● Oct. 11, 2026

As matter streams from the brown dwarf toward the star, it strikes the stellar surface at high speeds, generating an intensely heated region.

From Science Daily ● Oct. 10, 2026

But whether high-profile technology companies should devote so much of their extra cash to stock buybacks tends to be a topic of heated debate on Wall Street, and that’s true in Micron’s case as well.

From MarketWatch ● Oct. 5, 2026

The news-reading public used spirit gossip, spirit cartoons, and spirit love stories as distractions from the realization that there seemed to be no peaceful way forward on the increasingly heated issue of slavery’s expansion.

From "American Spirits" by Barb Rosenstock

In the Northeast, diesel also comes out of the same refined-oil pool as the heating oil used to heat homes in the winter, Carpenter said.

From MarketWatch ● Oct. 14, 2026

Proposed explanations have included differences in how the Moon's original magma ocean circulated, a massive collision, heating caused by gravitational tides, and uneven development of the lunar crust.

From Science Daily ● Oct. 14, 2026

The supply squeeze has complicated Europe’s efforts to replenish gas inventories ahead of the heating season, leaving the region increasingly exposed to colder weather and renewed competition with Asian buyers for available cargoes.

From The Wall Street Journal ● Oct. 13, 2026

U.S. natural gas futures fell as warmer weekend weather forecasts limit early-season heating demand.

From The Wall Street Journal ● Oct. 13, 2026

I sit with the dorks in the center back, by the long, rattling heating and air-conditioning unit.

From "Please Ignore Vera Dietz" by A.S. King

Related Words

• bake
• boil
• broil
• grill
• ignite
• melt
• reheat
• roast
• sear
• steam
• thaw
• toast
• warm