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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.

Sitting in her armchair, Angela glances up towards her son's photographs and says: "He's certainly given me a few sleepless nights, I can tell you. It's a wonder I'm not white!"

From BBC

This work requires stealth and sleepless nights to stalk poachers in the dark.

From BBC

Mia admits that, for the first time, the enormity of the detailing has caused sleepless nights.

From BBC

"It also normalises library use and, even if the admin involved in getting a library card isn't vast, it's one more thing to do when you're juggling nappies and sleepless nights."

From BBC

"The family broke. They are falling apart," his brother-in-law Rabbi Mendel Kastel told reporters after a sleepless night.

From BBC