an·​ti·​se·​rum | \ ˈan-tē-ˌsir-əm How to pronounce antiserum (audio) , ˈan-ˌtī- How to pronounce antiserum (audio) , -ˌser- \
plural antisera\ ˈan-​tē-​ˌsir-​ə How to pronounce antiserum (audio) , ˈan-​ˌtī-​ , -​ˌser-​ \ or less commonly antiserums

Definition of antiserum

: blood serum that contains antibodies against an infective agent (such as a bacteria or virus) or toxic substance (such as snake venom) and may be used to prevent or treat infection or poisoning

Note: Antiserum is obtained from individuals who have produced antibodies following inoculation with an antigen or recovery from an infection. Antiserum may be monovalent (containing antibodies against a single type of antigen or pathogenic agent) or polyvalent (containing antibodies against two or more types of antigens or pathogenic agents).

— compare antivenin, convalescent serum

Examples of antiserum in a Sentence

Recent Examples on the Web There are hardly any producers of antiserum left, however. Kai Kupferschmidt, Science | AAAS, "Scientists find way to make diphtheria treatment without injecting horses with toxin," 17 Jan. 2020

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

First Known Use of antiserum

1895, in the meaning defined above

History and Etymology for antiserum

International Scientific Vocabulary

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Time Traveler for antiserum

Time Traveler

The first known use of antiserum was in 1895

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Cite this Entry

“Antiserum.” Dictionary, Merriam-Webster, Accessed 1 Mar. 2021.

Style: MLA
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More Definitions for antiserum


an·​ti·​se·​rum | \ ˈant-i-ˌsir-əm How to pronounce antiserum (audio) , ˈan-ˌtī- How to pronounce antiserum (audio) , -ˌser- \

Medical Definition of antiserum

: a serum containing antibodies

called also immune serum

More from Merriam-Webster on antiserum Encyclopedia article about antiserum

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