蒸し暑い

「蒸し」は蒸気に関連し、「暑い」は温度が高いことを表す。

ADJ (1)

[/muɕi a̠tsɯi/^ja-JP]

hot and humid literal / muggy literal / sticky literalinformal / sweltering literal / unpleasantly warm and humid untranslatable (There isn't a direct equivalent that fully encapsulates the discomfort associated with both heat and humidity as in the original concept.)

Synonyms 暑苦しい informal , 湿気が多い formal

Antonyms 涼しい

This adjective describes weather that is not only hot but also very humid, creating a sense of discomfort, stickiness, or oppressiveness. It's commonly used to describe the typical summer climate in many parts of Japan, where the combination of high temperatures and high humidity makes the air feel thick and heavy. While English has terms like hot and humid, muggy, sticky, or sweltering, "蒸し暑い" uniquely emphasizes the combined unpleasantness of both heat and humidity.

plural
...

夏の日本の天気はとても蒸し暑いです。 — The summer weather in Japan is very hot and humid.
蒸し暑い夜だったので、エアコンをつけました。 — It was a muggy night, so I turned on the air conditioner.
今日は本当に蒸し暑くて、何もする気が起きない。 — It's truly hot and humid today, and I don't feel like doing anything.