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English definition of “melatonin”


noun [U]     /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 pattern Substances and structures in the body
(Definition of melatonin noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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