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
Examples of sleepless in a sentence
He lay sleepless in bed.
First Known Use of sleepless
SLEEPLESS Defined for English Language Learners
Definition of sleepless for English Language Learners
: without sleep
: not able to sleep
Seen and Heard
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