in vi·​vo | \ in-ˈvē-(ˌ)vō How to pronounce in vivo (audio) , -ˈwē-(ˌ)wō\

Definition of in vivo

: in the living body of a plant or animal

Examples of in vivo in a Sentence

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If a drug passes initial screening tests in vitro, researchers next test it in vivo in live animals to determine the effects of a new drug on a whole system instead of just one cell type at a time. Smithsonian, "How Putting Organs on Chips Could Revolutionize Medicine," 31 May 2018 On the question of whether CRISPR can be safely used in vivo, the stakes are high for many. Meghana Keshavan, STAT, "CRISPR paper that sent stocks tumbling is retracted," 30 Mar. 2018 If wider studies do, in fact, confirm that CCL11 can be used as a specific in vivo marker for CTE, then what? Jenny Vrentas,, "Diagnosing CTE: A Breakthrough Could Be Here ‘In the Next Five Years’," 27 Sep. 2017 Tissue clearing, in combination with in vivo bioluminescence, allows a three-dimensional scan of a whole organ, or a whole body, very quickly. Nathan Hurst, Smithsonian, "Transparent Mice Let Researchers See Cancer Spread in Real Time," 6 July 2017

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

1901, in the meaning defined above

History and Etymology for in vivo

New Latin, literally, in the living

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Time Traveler for in vivo

The first known use of in vivo was in 1901

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More Definitions for in vivo

in vi·​vo | \ in-ˈvē-(ˌ)vō How to pronounce in vivo (audio) \

Medical Definition of in vivo

1 : in the living body of a plant or animal in vivo synthesis of DNA microorganisms are not ordinarily destroyed in vivo by bacteriostatic drugsJournal of the American Medical Association
2 : in a real-life situation observing a patient's behavior in vivo

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