sleepless

adjective sleep·less \ ˈslēp-ləs \

Definition of sleepless

1 :not able to sleep
  • lay sleepless with fever
2 :affording no sleep
  • sleepless nights
3 :unceasingly active or operative
  • sleepless casinos

sleeplessly

adverb

sleeplessness

noun

Examples of sleepless in a Sentence

  1. He lay sleepless in bed.

Recent Examples of sleepless from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sleepless.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of sleepless

15th century


SLEEPLESS Defined for English Language Learners

sleepless

adjective

Definition of sleepless for English Language Learners

  • : without sleep

  • : not able to sleep


Medical Dictionary

sleepless

adjective sleep·less \ ˈslē-pləs \

medical Definition of sleepless

:not able to sleep :insomniac

sleeplessness

noun


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