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.

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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

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Other Word Forms

• sleeplessly adverb
• sleeplessness noun

Etymology

Origin of sleepless

late Middle English word dating back to 1375–1425; sleep, -less

Example Sentences

They simply show that a disciplined, diversified approach offers something rare in investing: higher odds of success with fewer sleepless nights.

From MarketWatch

But it is the opposite scenario—losing the AI race—that is giving them more sleepless nights these days.

From The Wall Street Journal

But, at the same time, they’re looking at enough of a payoff to risk a few sleepless nights.

From The Wall Street Journal

"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

Related Words

• fidgety