nightmare

3 definitions • 4 examples

a very upsetting or frightening dream:

a terrifying nightmare

I shouldn't have watched that movie - it'll give me nightmares.

an extremely unpleasant event or experience or possible event or experience:

The whole journey was a nightmare - we lost our luggage and both flights were delayed.

Being trapped underwater is my worst nightmare.

a very upsetting or frightening dream, or an extremely unpleasant event or experience