vac·​cine | \ vak-ˈsēn How to pronounce vaccine (audio) , ˈvak-ˌsēn \

Definition of vaccine

: a preparation of killed microorganisms, living attenuated organisms, or living fully virulent organisms that is administered to produce or artificially increase immunity to a particular disease

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Other Words from vaccine

vaccine adjective

Examples of vaccine in a Sentence

Recent Examples on the Web On Monday, Adar Poonawalla, chief executive of the Serum Institute of India, predicted there may not be enough Covid-19 vaccine until 2024. Eliza Mackintosh, CNN, "What you need to know about coronavirus on Thursday, September 17," 17 Sep. 2020 The head of the German Farmers Association expressed concern about the outbreak, noting that there is no vaccine available yet for the virus that causes African swine fever. Frank Jordans, Star Tribune, "Germany confirms 1st case of swine fever on its territory," 10 Sep. 2020 There may be a vaccine for COVID-19 in the months ahead, but the majority of people will have to take it for herd immunity to be achieved. Matthew Facciani, The Conversation, "Video: How did mask wearing become so politicized?," 9 Sep. 2020 By contrast, there is no comparable vaccine for tuberculosis. Dhruv Khullar, The New Yorker, "It Will Take More Than a Vaccine to Beat COVID-19," 8 Sep. 2020 However, the authors noted that participants were only followed for 42 days, the study sample was small and there was no placebo or control vaccine used. Joel Shannon, USA TODAY, "Coronavirus live updates: Cases spiked after previous holiday weekends; 'be careful,' Trump says," 6 Sep. 2020 This year’s flu season comes amid the ongoing COVID-19 pandemic, for which there is not yet a vaccine. Patrick Strickland, Dallas News, "Garland Public Health Clinic receives first shipment of flu vaccines," 3 Sep. 2020 There has yet to be a vaccine for the coronavirus that has been proven safe and effective through clinical trials, though many are in the late stages of development. Cassidy Morrison, Washington Examiner, "CDC asks states to prepare for vaccine distribution before Election Day," 2 Sep. 2020 The coronavirus pandemic is changing the face of the makeup business, but sales are expected to bounce back once there is a vaccine. Veronica Dagher, WSJ, "Beauty Stocks Face New Reality Amid Coronavirus Pandemic," 1 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'vaccine.' 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 vaccine

1882, in the meaning defined above

History and Etymology for vaccine

earlier, "fluid from cowpox pustules used in inoculation," noun use of vaccine "of cowpox" (in the phrases vaccine disease, vaccine matter), borrowed from New Latin vaccina (in variolae vaccinae "cowpox"), going back to Latin, feminine of vaccīnus "of or from a cow," from vacca "cow" (perhaps akin to Sanskrit vaśā "cow") + -īnus -ine entry 1; in extended sense, "preparation of organisms administered to produce immunity," in part borrowed from French vaccin, masculine derivative of vaccine "cowpox, matter from cowpox pustules," borrowed from New Latin or English

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Time Traveler for vaccine

Time Traveler

The first known use of vaccine was in 1882

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Statistics for vaccine

Last Updated

25 Sep 2020

Cite this Entry

“Vaccine.” Dictionary, Merriam-Webster, Accessed 30 Sep. 2020.

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More Definitions for vaccine


How to pronounce vaccine (audio)

English Language Learners Definition of vaccine

medical : a substance that is usually injected into a person or animal to protect against a particular disease


vac·​cine | \ vak-ˈsēn How to pronounce vaccine (audio) , ˈvak-ˌsēn \

Kids Definition of vaccine

: a preparation containing usually killed or weakened microorganisms (as bacteria or viruses) that is given usually by injection to increase protection against a particular disease


vac·​cine | \ vak-ˈsēn, ˈvak-ˌ How to pronounce vaccine (audio) \

Medical Definition of vaccine

1 : matter or a preparation containing the virus of cowpox used to vaccinate a person against smallpox
2 : a preparation of killed microorganisms, living attenuated organisms, or living fully virulent organisms that is administered to produce or artificially increase immunity to a particular disease chicken pox vaccine also : a mixture of several such vaccines measles-mumps-rubella vaccine

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More from Merriam-Webster on vaccine

Nglish: Translation of vaccine for Spanish Speakers

Britannica English: Translation of vaccine for Arabic Speakers Encyclopedia article about vaccine

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