熱（ねつ、netsu）
- fever

The Japanese word 熱 (ねつ, netsu) has several meanings, all related to the concept of heat or passion. It's a versatile word, and its specific meaning depends on the context. ⚫︎ It can refer to physical heat, like the temperature of something or someone. ⚫︎ It can also describe a fever, an elevated body temperature due to illness. ⚫︎ Furthermore, 熱 can represent passion, enthusiasm, or strong feelings toward something. In this sense, it conveys a sense of intensity and fervor. ⚫︎ The kanji 熱 itself depicts "heat" or "hot" (temperature).

⚫︎ 熱いお湯 Translation: Hot water ⚫︎ 彼女は熱がある Translation: She has a fever. ⚫︎ 熱心なファン Translation: Enthusiastic fan

⚫︎ Use 熱 when talking about temperature. ⚫︎ Use 熱 to describe a fever. ⚫︎ Use 熱 when expressing strong feelings or enthusiasm about a topic, hobby, or person. ⚫︎ When speaking about physical heat, it often pairs with other words to provide additional context. For example, 熱い (atsui), meaning "hot," is a common adjective used with 熱. ⚫︎ The word also takes the form of verbs like 熱する (nessuru, "to heat") or nouns such as 熱度 (netsudo, "degree of heat").

⚫︎ The word is primarily written using the kanji 熱. ⚫︎ The reading, ねつ (netsu), is written in hiragana. ⚫︎ The okurigana (hiragana following the kanji) may vary depending on the conjugation of a verb form. For example, 熱する (nessuru) and 熱い (atsui).

⚫︎ 高温 (kōon): high temperature ⚫︎ 発熱 (hatsu netsu): fever ⚫︎ 情熱 (jōnetsu): passion ⚫︎ 熱意 (netsui): enthusiasm ⚫︎ 暑さ (atsusa): heat (as in the weather)

⚫︎ 冷たい (tsumetai): cold ⚫︎ 寒さ (samusa): cold (as in the weather) ⚫︎ 無関心 (mukanshin): indifference

今日は熱が出て、学校を休んだ。 ・Translation: I had a fever today, so I stayed home from school. ・Explanation: This sentence uses 熱 to indicate a fever, a rise in body temperature.

彼はサッカーに熱心で、毎日練習している。 ・Translation: He is passionate about soccer and practices every day. ・Explanation: In this case, 熱 expresses passion or enthusiasm for soccer.

The kanji 熱 is composed of two parts: the radical 火 (hi), meaning "fire," and 執 (shū), which can imply holding or grasping. The combination suggests something being held by fire, hence the association with heat and intensity.