sleepless
Americanadjective
-
without sleep.
a sleepless night.
-
watchful; alert.
sleepless devotion to duty.
-
always active.
the sleepless ocean.
adjective
-
without sleep or rest
a sleepless journey
-
unable to sleep
-
always watchful or alert
-
poetic always active or moving
the sleepless tides
Other Word Forms
- sleeplessly adverb
- sleeplessness noun
Etymology
Origin of sleepless
late Middle English word dating back to 1375–1425; sleep, -less
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
But it is the opposite scenario—losing the AI race—that is giving them more sleepless nights these days.
But, at the same time, they’re looking at enough of a payoff to risk a few sleepless nights.
"It was a sleepless night to defuse more bombs in the region... the communication is still underway to consolidate the gained trust and the current good spirit."
From Barron's
She worries about years of chronic stress and sleepless nights – as well as the additional physical and psychological trauma for those on the front line.
From BBC
I am left exhausted from my sleepless night with one nugget of a thought stuck in my jowls: That I’m ashamed of how angry I was at the pups and my parents.
From Literature
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.