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English definition of “serum”


noun [C or U] (BEAUTY PRODUCT)    /ˈsɪə.rəm/ US  /ˈsɪr.əm/ (plural sera   /ˈsɪə.rə/   US  /ˈsɪr.ə/ or serums)
a substance in beauty products that is designed to improve your hair or skin and make it less dryBeauty treatments
(Definition of serum noun (BEAUTY PRODUCT) from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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