in a bad mood and not speaking, either on a particular occasion or because it is part of your character 面有愠色的；悶悶不樂的；鬱鬱寡歡的 Bob looked pale and sullen. 鮑勃臉色蒼白，悶悶不樂。 She gave him a sullen glare. 她滿臉不高興地瞪了他一眼。 sullen teenagers 面色陰鬱的青少年 He lapsed into a sullen silence. 他陷入了陰鬱的沉默。
- (literary)
(of the sky or weather 天空或天氣 dark and unpleasant 陰沉的 a sullen grey sky 陰沉的灰色天空
Word OriginMiddle English (in the senses ‘solitary, averse to company’, and ‘unusual’): from Anglo-Norman French sulein, from sol ‘sole’.