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English definition of “insomnia”


noun [U]     /ɪnˈsɒə/ US  /-ˈsɑːm-/
C2 the condition of being unable to sleep, over a period of time: Holly suffered from insomnia caused by stress at work.Not sleeping and not unconscious
(Definition of insomnia noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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