the world > the earth > weather and the atmosphere > weather > bad weather > [noun] > oppressive stillness or closeness (4)
Heaviness of the air, sky, etc.; absence of life and motion, oppressive stillness.
Want of free air or ventilation, as in a room that is shut up; a similar quality of the atmosphere in still sultry weather.
The state, quality, or condition of being muggy; (esp. of weather) humidity.