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

That window shortens to one hour if air conditioning fails during summer heat.

From The Wall Street Journal ● Aug. 8, 2026

An extreme heat warning was in place for the high desert, with temperatures potentially reaching 112 degrees in the Antelope Valley and 120 in the Mojave Desert.

From Los Angeles Times ● Aug. 8, 2026

Yellow heat health alerts have been issued for most of England until Tuesday, warning of impacts for health and social care services and an increased risk to life for vulnerable people.

From BBC ● Aug. 8, 2026

Cafes, shops and big apartment blocks were bustling with activity in the baking Athens heat.

From BBC ● Aug. 7, 2026

Her face was flushed from the heat and the effort.

From "Earthquake Terror" by Peg Kehret

As the Sun heats the ground, the water vapour suddenly condenses.

From Barron's ● Jul. 27, 2026

As that warm blob of ocean water hugs the coast of South America, it heats the air above, causing the pressure to drop.

From Los Angeles Times ● Jul. 22, 2026

Front-month gold and silver settled higher, getting a boost as equities also rose on strength in technology shares as earnings season heats up.

From The Wall Street Journal ● Jul. 21, 2026

But a hand injury blighted his chances of being named 2026 World's Strongest Man, and he was knocked out in the qualifying heats.

From BBC ● Jul. 20, 2026

That heats me more than the whole conversation up until then.

From "X: A Novel" by Ilyasah Shabazz

Pirro brought a box of documents to make her case, and the meeting got heated, but ultimately, so far, she still has a job.

From Slate ● Aug. 4, 2026

In this process, fine WC and Co powders are compressed under high pressure and heated in sintering machines.

From Science Daily ● Aug. 4, 2026

Homeowners have to rip up their whole bathroom or driveway if something goes wrong with their heated floors, Christian Perry, a Greenwich, Conn.-based real-estate agent, told MarketWatch.

From MarketWatch ● Aug. 1, 2026

Part of their unofficial relationship homework involves field missions that spark heated conversations about masculine insecurity and Diarra’s conflicted desires about motherhood.

From Salon ● Aug. 1, 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

Instead of heating the material to drive out the water, the team tested what would happen if the water remained.

From Science Daily ● Aug. 1, 2026

A wholesale distributor of plumbing, heating and other products for construction trades is set to become the newest member of the S&P 500 index.

From MarketWatch ● Jul. 31, 2026

The fires burning through parts of France and Spain haven’t yet been extinguished, but the blame game is already heating up.

From The Wall Street Journal ● Jul. 30, 2026

"I had to think twice before putting my heating on," she says.

From BBC ● Jul. 29, 2026

It had two lids and doubled for cooking and heating.

From "Sounder" by William H. Armstrong

Related Words

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