暑

A phono-semantic compound composed of:

日 (sun) — semantic component, indicating heat and sunlight

者 (person; one who) — phonetic component (shǔ)

The character expresses the idea of a person exposed to the blazing sun, conveying intense heat rather than warmth in general. From this, the meaning naturally extended to summer heat and hot seasons.

暑中 (서중) — midsummer

酷暑 (혹서) — extreme heat

避暑 (피서) — escaping the heat; summer retreat

暑氣 (서기) — summer heat; heat in the air

暑 denotes intense, seasonal heat, especially the oppressive heat of summer.

It differs from 熱 (열):

暑 — seasonal or climatic heat (summer heat)

熱 — heat in general, fever, passion, thermal energy

Related characters:

夏 — summer (season itself)

熱 — heat; fever; passion

炎 — blaze; scorching heat

暖 — warm (moderate warmth)

In Korean hanja, there is an additional 丶 stroke above 日 in the component 者, which is also the historical form found in the Kangxi dictionary.

A CJK compatibility ideograph (U+FA43) exists for the Japanese kyūjitai form which is similar to the form above.