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

One of them is the use of this experimental Ebola vaccine at this scale. Julia Belluz, Vox, "Why the Ebola outbreak in DRC is so difficult to contain," 2 Dec. 2018 Meanwhile, coverage of the crucial second dose of the vaccine is only at 67 percent worldwide. Cathleen O'grady, Ars Technica, "The fight against measles has taken a turn for the worse," 30 Nov. 2018 Still, more than 18,000 people have received the experimental Ebola vaccine, the WHO said, making it by far the largest immunization campaign ever against the virus. Nicholas Bariyo, WSJ, "WHO Calls for More Resources to Fight Ebola Outbreak," 17 Oct. 2018 Health experts said the use of a still-experimental vaccine on more than 3,300 people was a major factor in containing the outbreak, Congo’s ninth since the hemorrhagic fever was first identified in 1976. Saleh Mwanamilongo, The Seattle Times, "Congo confirms end of latest deadly Ebola outbreak," 24 July 2018 In addition to ZMapp and other drugs, an experimental vaccine made by Merck is now being used to prevent the spread of Ebola. Bradley J. Fikes,, "San Diego scientists fight latest Ebola outbreak," 23 May 2018 Congo to begin vaccinating against Ebola Congo will begin administering an experimental Ebola vaccine Monday in Mbandaka, the northwestern city of 1.2 million where the deadly disease has infected some residents, Congo’s health minister announced. Editors, USA TODAY, "Texas school shooting, Trump calls for FBI investigation: 5 things you need to know Monday," 21 May 2018 This experimental vaccine can only be used in the context of a clinical trial. Dina Fine Maron, Scientific American, "Everything You Need to Know about the Ebola Vaccine," 17 May 2018 On Friday, the World Health Organization announced its plan to send the experimental vaccine to northwest Congo, where there have been about 32 suspected or confirmed cases since early April, and 18 deaths. Siobhán O'grady,, "A pioneering vaccine is being sent to Congo in hopes of containing a new Ebola outbreak," 11 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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11 Dec 2018

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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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More from Merriam-Webster on vaccine

Rhyming Dictionary: Words that rhyme with vaccine

Spanish Central: Translation of vaccine

Nglish: Translation of vaccine for Spanish Speakers

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

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the figure or shape of a crescent moon

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