Translation guide
The English word "heat" covers a wide range of meanings, from physical warmth to emotional intensity and sports rounds. This guide breaks down the most useful Japanese expressions for each context.
Referring to the physical quality of being hot, or the sensation of warmth.
Used for atmospheric heat, especially hot weather. This is the most common word for heat you feel in the air.
今日の暑さは耐えられない。
I can't stand today's heat.
Refers to heat as a form of energy, or the heat of an object, fever, or passion. More scientific or internal than 暑さ.
The degree or sensation of heat from an object, like food or a surface. Less common than 暑さ for weather.
このスープの熱さにびっくりした。
I was surprised by the heat of this soup.
High temperature, often used in technical or formal contexts.
The act of making something hot, or a device used for heating.
Emotional heat, such as anger, enthusiasm, or pressure.
Enthusiasm, zeal, passion. Positive emotional heat.
The feeling of being under pressure or scrutiny.
A preliminary contest to qualify for the next stage.
Preliminary round, qualifying heat.
The sensation of heat from spicy food.
Spiciness, hotness (from chili, etc.). Not temperature heat.
このカレーの辛さはちょうどいい。
The heat of this curry is just right.
The period when a female animal is ready to mate.
暑さ (atsusa) is for atmospheric/weather heat. 熱 (netsu) is for heat as energy, fever, or passion. 熱さ (atsusa) is the tangible heat of an object. Using the wrong one can sound odd.
夏の暑さは厳しい。
The summer heat is severe.
摩擦で熱が発生する。
Heat is generated by friction.
お風呂の熱さを確かめる。
Check the heat of the bath.
今日は暑さがたまらない。
The heat is unbearable today.
彼は200m予選に出場した。
He entered the 200m heat.
このチリの辛さが好きだ。
I like the heat of this chili.
This metal conducts heat well.
熱がある。
I have a fever. (lit. There is heat.)
高温注意。
Caution: high temperature.
Heating (system) for a room or building. Not for cooking.
暖房をつけてください。
Please turn on the heat.
The process of applying heat, especially in cooking or science.
加熱時間は5分です。
Heating time is 5 minutes.
Literally 'fire', but often used for cooking heat. 'Heat' in recipes is often 火.
弱火で10分煮る。
Simmer on low heat for 10 minutes.
彼の熱意が伝わってきた。
I could feel his passion/enthusiasm.
Heated atmosphere, excitement in a crowd or event.
会場の熱気に圧倒された。
I was overwhelmed by the heat/excitement of the venue.
Intensity, fierceness. Can be used for heated arguments or competition.
議論の激しさに驚いた。
I was surprised by the heat of the argument.
To get angry, to lose one's temper. Literally 'come to the head'.
彼の態度には本当に頭にくる。
His attitude really makes my blood boil.
Loanword from English, very common for psychological pressure.
試合前はすごいプレッシャーを感じる。
I feel a lot of heat/pressure before a match.
Pressure, often from external forces or authority.
上司からの圧力に耐えられない。
I can't take the heat from my boss.
彼は100m予選で1位になった。
He placed first in the 100m heat.
Pungent taste, spiciness. Often used in food descriptions.
辛味が強い料理が好きだ。
I like dishes with a lot of heat.
Mating season, estrus. Technical/biological term.
猫の発情期は春です。
Cats are in heat in spring.
When talking about spicy food, use 辛さ (karasa) or 辛味 (karami). Using 熱 (netsu) or 暑さ (atsusa) would mean temperature heat, not spiciness.
When talking about spicy food, use 辛さ (karasa) or 辛味 (karami). Using 熱 (netsu) or 暑さ (atsusa) would mean temperature heat, not spiciness.