SLEEPLESS Synonyms: 34 Similar and Opposite Words

sleepless

adjective

ˈslēp-ləs

Definition of sleepless

as in wakeful

not sleeping or able to sleep lay sleepless with worry

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Antonyms & Near Antonyms

Example Sentences

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Recent Examples of sleepless Nelson remembers hushing her foster children back to sleep that night and calling 911, anxious for an end to those sleepless nights. — Kendrick Calfee, Kansas City Star, 2 Sep. 2026 This month, her mother’s memory-care facility was in an evacuation zone, causing many sleepless nights. — Anya Kamenetz, Curbed, 28 Aug. 2026 The London musician’s forlorn and otherworldly new industrial track passes a sleepless night. — Marshall Gu, Pitchfork, 28 Aug. 2026 Like most expectant parents, Briana Faucette heard the typical warnings about sleepless nights. — Roni Robbins, AJC.com, 20 July 2026 See All Example Sentences for sleepless

Recent Examples of Synonyms for sleepless

Adjective

These ripples are associated with spikes of activity in the prefrontal cortex, and scientists only observe them during periods of sleep or quiet, wakeful rest.

— Sean Mccabe, Hartford Courant, 18 Oct. 2026
In a previous university blog post, Majumdar compared this finding to the brain flushing out byproducts that build up during active, wakeful moments, allowing for a more restful night’s sleep.

— Mack DeGeurin, Popular Science, 9 Sep. 2026

Definition of wakeful

Adjective

Just one day earlier, he was diagnosed with a superficial blood clot in his left calf and ordered by doctors to stay awake overnight, according to NFL insiders, who report the quarterback did not sleep for roughly 36 hours.

— Mark Osborne, CBS News, 20 Oct. 2026
The exact story of how coffee was discovered isn’t known for sure, but one popular legend says an Ethiopian goatherd named Kaldi noticed that when his goats ate from a red berry plant, they were infused with energy and stayed awake all night.

— Olivia Wakim, AJC.com, 18 Oct. 2026