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serum - definition and synonyms


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noun medical serum pronunciation in British English /ˈsɪərəm/
Word Forms
pluralserums or sera
  1. 1
    [countable/uncountable] a liquid that is put into someone’s blood to help them to fight an infection or a poison
  2. 2
    [uncountable] the thin yellow liquid that is part of blood and that separates from it when it clots (=becomes thick and hard)


a title used before a man or woman's name as a gender-neutral alternative to Mr, Ms, etc

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another way of saying congratulations, or that something/someone looks nice or fascinating

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