Definition of worst nightmare
- Losing a child is every parent's worst nightmare.
: superlative of bad
: or of ill
: most corrupt, bad, evil, or ill
: superlative of ill
: or illy
: or of bad
: one that is worst
: to get the better of : defeat
: an evil spirit formerly thought to oppress people during sleep
: a frightening dream that usually awakens the sleeper
: something (such as an experience, situation, or object) having the monstrous character of a nightmare or producing a feeling of anxiety or terror
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