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English definition of “melatonin”


noun [U] uk   /mel.əˈtəʊ.nɪn/ us    /-ˈtoʊ-/ specialized
a hormone in the body that produces changes in skin colour and is involved in continuing biorhythms such as our sleep patternSubstances and structures in the body
(Definition of melatonin from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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