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.
Francisco Gonzalez, a 79-year-old retiree, also said he had a sleepless night in the dark, "sitting in an armchair at home, waiting for the power to come back on."
From Barron's • Mar. 22, 2026
They simply show that a disciplined, diversified approach offers something rare in investing: higher odds of success with fewer sleepless nights.
From MarketWatch • Feb. 5, 2026
But, at the same time, they’re looking at enough of a payoff to risk a few sleepless nights.
From The Wall Street Journal • Jan. 16, 2026
Perhaps no one in Los Angeles is as driven to win as Cronin, who has mused about sleepless nights and the miserable existence associated with losing.
From Los Angeles Times • Jan. 8, 2026
And then she said something that guaranteed Citra many a sleepless night.
From "Scythe" by Neal Shusterman
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.
