heavy (feeling, etc.); gloomy (weather, etc.); oppressive (atmosphere, etc.); stifling; strained
重苦しい雰囲気が部屋を包んでいた。
A heavy atmosphere hung over the room.
長引く会議の空気は重苦しかった。
The atmosphere of the drawn-out meeting was oppressive.
重苦しく垂れこめた雲が一日中空を覆っていた。
Heavy, low-hanging clouds covered the sky all day.