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Synonyms

sleepless

American  
[sleep-lis] / ˈslip lɪs /

adjective

  1. without sleep.

    a sleepless night.

  2. watchful; alert.

    sleepless devotion to duty.

  3. always active.

    the sleepless ocean.


sleepless British  
/ ˈsliːplɪs /

adjective

  1. without sleep or rest

    a sleepless journey

  2. unable to sleep

  3. always watchful or alert

  4. poetic  always active or moving

    the sleepless tides

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

"These results, they come from hard work in the dark, a lot of sleepless nights trying to figure out how to master my craft and be more consistent with my jump shot."

From Barron's

Figuring out how to absorb these costs has led to “more than a few sleepless nights,” she said.

From Salon

What followed was a sleepless night for Seoul.

From BBC

A Welsh farmer has had sleepless nights and been left feeling "angry and scared" since changes to inheritance tax rules were announced.

From BBC

With nowhere else to go, Hassan took his family to the seaside, where they spent a sleepless night squeezed together in the car.

From BBC