How to say "heat" in Japanese

• 熱ねつJLPT N4approx.Common
  nounThe basic noun for heat: high temperature, or fever in the body. Use it when heat is a thing or condition, as in the heat of the day or having a fever.
  熱ねつによって氷こおりは水みずに変かわる。↗

  Heat turns ice into water.
• 温めるあたためるJLPT N2approx.Common
  ichidan verb, transitive verbA verb meaning to warm something up or heat it gently, typically food or a drink. It suggests raising the temperature to a comfortable degree rather than making it very hot.
  ミルクを温あたためてくれませんか。↗

  Will you warm the milk, please?
• ヒートCommon
  nounThe loanword for heat, mostly found in fixed expressions such as sports or technical terms. It is seldom the everyday word you want; 熱 is the usual noun for heat.
• 熱するねっするJLPT N2approx.Common
  suru verb (irregular), transitive verb, intransitive verbA verb meaning to heat or heat something up, often to a high temperature. It sounds more technical or formal than 温める, as in heating a pan or a substance.
  水みずは熱ねっせられると蒸気じょうきになる。↗

  Water changes into vapor when it is heated.
• 熱気ねっきCommon
  nounHeat as hot air radiating from something, or figuratively an excited, heated atmosphere, such as the hot air from a stove or the fervor of a crowd.
  その部屋へやは参加者さんかしゃの熱気ねっきでムンムンしていた。↗

  The air in that room was thick with the enthusiasm of the participants.

Use 熱 for heat as a noun (fever, high temperature), 熱気 for hot air or an atmosphere, and the verbs 「温める」 or 「熱する」 for heating something up; 「ヒート」 is a loanword used mainly in set phrases.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 熱ねつheat
• 温めるあたためるto warm (up)
• ヒートheat
• 熱するねっするto heat
• 熱気ねっきheat
• 沸かすわかすto boil
• 暑さあつさheat (of the weather)
• 温熱おんねつwarmth
• 予選よせんpreliminary contest
• 温めるぬくめるto warm (up)
• 温気うんきheat
• 火熱かねつheat (from a flame)
• 熱さあつさheat (of a thing)
• 暑しょheat
• 加温かおんheating
• 火照りほてりa glow
• 火を通すひをとおすto cook
• 発情はつじょうsexual excitement
• 焼くやくto heat
• 焚くたくto heat (a bath)
• 火の気ひのけwarmth of fire
• 盛りさかり(being in) heat