Definition of “sleepless” - English Dictionary

“sleepless” in British English

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(Definition of “sleepless” from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)

“sleepless” in American English

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sleeplessadjective [ not gradable ]

us /ˈslip·ləs/

without sleeping, or without being able to sleep:

I’ve spent so many sleepless nights worrying about him.

(Definition of “sleepless” from the Cambridge Academic Content Dictionary © Cambridge University Press)