Serum

/ˈsɪərəm/
C1

Definition, CEFR level C1, pronunciation, examples, and quiz.

Listen pronunciation

nounA clear liquid part of blood, used in medical tests or treatments.

Extra definitions

nounA concentrated skin-care product.

nounEllipsis of blood serum.

nounBlood serum used as a blood product, in the practice of medicine: blood serum from the tissues of immunized animals (human or nonhuman), containing antibodies and used to transfer immunity to another individual (human or nonhuman).

The laboratory tested the serum.
The patient received serum.
She applies vitamin serum.
Synonyms:
None
Antonyms:
None

From Latin serum (“whey”). Cognates include French sérum, Spanish suero, Italian siere, siero, Portuguese soro. Doublet of suero.

CEFR Practice Quiz
The laboratory tested the ____.

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