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English definition of “sleepless”

sleepless

adjective [before noun] uk   /ˈsliːp.ləs/ us  
C1 without any sleep: I've spent so many sleepless nights worrying about him.Not sleeping and not unconscious [after verb] not able to sleep: Alone and sleepless, she stared miserably up at the ceiling.Not sleeping and not unconscious
sleeplessness
noun [U] uk   /-nəs/ us  
(Definition of sleepless from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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