vac·cine | \vak-ˈsēn, 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

In the event of a vaccine-preventable disease outbreak, such as chickenpox, students with exemptions will not be able to attend school until the outbreak is contained or the child is vaccinated. Arlinda Smith Broady, ajc, "Four questions about back-to-school vaccinations," 10 July 2018 These communities opt out of vaccines at a higher rate, and a number are now also skipping the vitamin K shot: two studies have found refusal rates are higher at birthing centers than hospitals. Renee Diresta, WIRED, "The Complexity of Simply Searching for Medical Advice," 3 July 2018 That information could help speed the development of a vaccine. Elizabeth Pennisi, Science | AAAS, "A koala’s diet would kill most mammals. Their genome reveals how they survive," 2 July 2018 In 2015, medical staff at the Dilley mistakenly gave adult doses of the hepatitis A vaccine to about 250 children. Melissa Fletcher Stoeltje, Houston Chronicle, "Some immigrant families have long been allowed to stay together," 20 June 2018 And in those states, the high exemption rate is putting kids at risk for contracting and spreading vaccine-preventable pediatric diseases including whooping cough and measles. Brittany Shoot, Fortune, "These Are the Riskiest Cities and Counties For Infectious Disease Epidemics," 14 June 2018 And at the same time, there was skepticism about the quality of the vaccine. Naseem S. Miller,, "Doctors push for higher HPV vaccination rates," 13 June 2018 While rabies can be fatal once clinical signs appear, it can be prevented through timely medical treatment that includes administration of one dose of immune globulin (antibodies) and four doses of vaccine over two weeks. Courant Community, "Community News For The Putnam-Killingly Edition," 12 June 2018 Their position on the dangers of vaccines keeps changing. Jason Horowitz,, "Italy’s populists get a green light to govern; some see a threat to EU," 23 May 2018

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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Statistics for vaccine

Last Updated

16 Oct 2018

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Time Traveler for vaccine

The first known use of vaccine was in 1882

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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, 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 \

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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Comments on vaccine

What made you want to look up vaccine? Please tell us where you read or heard it (including the quote, if possible).


to teach someone the beliefs of a group

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