кошмар

Кошмар means “nightmare”: a frightening or disturbing dream. In everyday Russian, it is also commonly used figuratively for something awful, stressful, chaotic, or unbelievable—similar to “a nightmare,” “horrible,” or “what a mess!” in English.

It comes through Russian from French cauchemar, ultimately connected to an old Germanic word for a night-demon or oppressive spirit believed to sit on sleepers’ chests. Informal reactions include ужас (“horror”), кошмарик (“little nightmare,” sometimes playful), and это жесть (“that’s brutal/insane,” slang; not an exact synonym).

1. Мне приснился кошмар.
   I had a nightmare.
2. Этот ремонт — настоящий кошмар.
   This renovation is a real nightmare.
3. Кошмар, я забыл ключи дома!
   What a nightmare, I forgot my keys at home!
4. После этого фильма мне всю ночь снились кошмары.
   After that movie, I had nightmares all night.
5. Очередь в аэропорту была просто кошмаром.
   The line at the airport was simply a nightmare.