Dictionary

An adult female horse.

A foolish woman.

A type of evil spirit formerly thought to sit on the chest of a sleeping person; also, the feeling of suffocation felt during sleep, attributed to such a spirit.

A demon or monster, thought to plague people while they slept and cause a feeling of suffocation and terror during sleep.

Sleep paralysis.

A very bad or frightening dream.

Example: I had a nightmare that I tried to run but could neither move nor breathe.

Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure.

Example: Cleaning up after identity theft can be a nightmare of phone calls and letters.