adj
sleepless
SLEEP-luhs
adj
1
Unable to sleep, or marked by an absence of sleep.
"She spent a sleepless night worrying about the interview."
"After three sleepless nights, he finally saw a doctor about the pain."
How to Use Sleepless
Learner’s notesIn plain EnglishWithout sleep — describing a night, or a person who can't sleep.
Common pairings
sleepless night
sleepless nights
Word Forms
more sleepless comparative, most sleepless superlative
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She spent a _____ night worrying about the interview.
Etymology
From Old English slǣplēas, literally "sleep" plus "-less" ("without").