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English definition of “hypersomnia”


noun [U] uk   /ˌhaɪ.pəˈsɒə/ us    /ˌhɑɪ.pərˈsɑə/ specialized
a sleep disorder in which someone sleeps for very long periods and is always very tired during the daySleep and sleeping
(Definition of hypersomnia from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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