nightmare
US /ˈnaɪt.mer/
UK /ˈnaɪt.mer/

1.
악몽
a terrifying dream in which the dreamer experiences feelings of helplessness, extreme anxiety, or sorrow
:
•
I woke up in a cold sweat after having a terrible nightmare.
끔찍한 악몽을 꾸고 식은땀을 흘리며 깨어났다.
•
Children often have nightmares about monsters.
아이들은 종종 괴물에 대한 악몽을 꾼다.