i-adjective
sultry; sweltering; oppressively hot
Describes weather or a room that feels uncomfortably hot and humid, often with a sense of stuffiness.
今日は本当に暑苦しい日だ。
Today is a really sultry day.
窓を閉めていると部屋が暑苦しくなる
The room gets stuffy when the windows are closed.
i-adjective
uncomfortably hot-looking; stuffy-looking
Used for clothing, accessories, or appearances that look too warm or stifling for the weather.
真夏にそのセーターは暑苦しい。
That sweater looks uncomfortably hot in midsummer.