Definition of worst nightmare
: the thing someone fears most Losing a child is every parent's worst nightmare.
Word by Word Definitions
: superlative ofbador ofill
: most corrupt, bad, evil, or ill
: most unfavorable, difficult, unpleasant, or painful
: superlative ofillorillyor ofbadorbadly
: to the extreme degree of badness or inferiority
: to the greatest or highest degree
: 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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