serum

noun
se·rum | \ˈsir-əm \
plural sera\ˈsir-ə \ or serums

Definition of serum 

(Entry 1 of 2)

1 : the watery portion of an animal fluid remaining after coagulation:

a(1) : blood serum

(2) : antiserum

b : whey

c : a normal or pathological serous fluid (as in a blister)

2 : the watery part of a plant fluid

3 : a usually lightweight cosmetic preparation especially for use on the face specifically : a typically water-based, often concentrated preparation that lacks lubricating and thickening agents an antiaging facial serum

serum

adjective

Definition of serum (Entry 2 of 2)

: occurring or found in the blood serum serum cholesterol serum antibodies

Examples of serum in a Sentence

Noun

The patient was administered serum.

Recent Examples on the Web: Noun

Forgo the sheet masks and serums Wednesday night to take part in this selfless act that contributes to the self-care of others. Kasia Pilat, New York Times, "7 Comedy Shows to Catch in N.Y.C. This Weekend," 12 July 2018 But fast-forward to my twenties, and it's been a real joy not having to spend the time and money trying to finding the best brow growth serum. Lindsay Schallon, Glamour, "This $10 Pen Makes It Look Like You Microbladed Your Brows," 11 June 2018 The items are part of the $200 billion round of import taxes that broadened trade hostilities that began July 6 with a U.S. list targeting $34 billion in trade including flamethrowers, fetal bovine serum and blood. Dave Mccombs And Andrew Hobbs, chicagotribune.com, "Badger hair, bull semen, MSG among products on Trump's China tariff list," 11 July 2018 Some rummaging around, Muyldermans says, turned up an alternative: a stash of frozen dromedary camel serum collected to study the animals' parasites. Mitch Leslie, Science | AAAS, "Mini-antibodies discovered in sharks and camels could lead to drugs for cancer and other diseases," 10 May 2018 Unfortunately for the Schmidt, the serum backfired and gave him, well, a red skull. Eliana Dockterman, Time, "An Old Marvel Villain Makes a Surprising Cameo in Avengers: Infinity War," 27 Apr. 2018 While interviewing Korean girl group EXID, three words, in particular, didn't require a translator: toner, serum, and Vaseline. Devon Abelman, Allure, "Hani of K-Pop Group EXID Reveals Her Simple Routine for Getting Glass Skin," 2 July 2018 Apply to Clean Skin, at Night Regardless of the formula, apply your toner or serum after cleansing, preferably at night, since exfoliating can make your complexion sun-sensitive. New York Times, "How to Exfoliate, Without Damaging Your Skin," 29 May 2018 This serum from skincare guru to the stars Joanna Vargas is a good bet. Kathleen Mulpeter, Health.com, "The Best Anti-Aging Products to Buy at the Dermstore Sale," 27 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'serum.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of serum

Noun

1665, in the meaning defined at sense 1

Adjective

1876, in the meaning defined above

History and Etymology for serum

Noun

Latin, whey, wheylike fluid; akin to Greek oros whey

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Statistics for serum

Last Updated

11 Oct 2018

Look-up Popularity

Time Traveler for serum

The first known use of serum was in 1665

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More Definitions for serum

serum

noun

English Language Learners Definition of serum

medical : the part of blood that is like water and that contains substances (called antibodies) that fight disease

medical : serum from an animal's blood that can be added to a person's blood to prevent or cure disease

biology : the watery part of a fluid found in a plant

serum

noun
se·rum | \ˈsir-əm \

Kids Definition of serum

: the clear liquid part that can be separated from coagulated blood and contains antibodies

serum

noun
se·rum | \ˈsir-əm \
plural sera\ \ or serums

Medical Definition of serum 

(Entry 1 of 2)

: the watery portion of an animal fluid remaining after coagulation:

a(1) : the clear yellowish fluid that remains from blood plasma after fibrinogen, prothrombin, and other clotting factors have been removed by clot formation

called also blood serum

(2) : antiserum

b : a normal or pathological serous fluid (as in a blister)

serum

adjective

Medical Definition of serum (Entry 2 of 2)

: occurring or found in the serum of the blood serum cholesterol serum glutamic-oxaloacetic transminase

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Comments on serum

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