Definition of "nightmare"
noun:
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A female demon or monster, thought to plague people while they slept and cause a feeling of suffocation and terror during sleep.
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A very bad or frightening dream.
from Wiktionary, Creative Commons Attribution/Share-Alike License -
Any bad, miserable, difficult or terrifying situation or experience that arouses anxiety, terror, agony or great displeasure.
from Wiktionary, Creative Commons Attribution/Share-Alike License
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