in vivo
adverb or adjective
in vi·vo
in-ˈvē-(ˌ)vō 
-ˈwē-(ˌ)wō
: in the living body of a plant or animal
Examples of in vivo in a Sentence
Recent Examples on the Web
Legend Biotech emerged as a rare market winner Shares of Legend Biotech soared over 40% yesterday after the company disclosed early data on its in vivo CAR-T therapy that showed promise in Non-Hodgkin’s lymphoma.
—
Elaine Chen, STAT, 3 June 2026
The scientific community is acutely aware of this, and research priorities are now pivoting toward next-generation in vivo gene-editing approaches where the editing machinery is delivered directly into the body to target the hematopoietic stem cells in situ.
—Tanya Lewis, Scientific American, 5 May 2026
The genetic root cause of the disease, edited in place, in vivo, inside a living human body.
—Jon Markman, Forbes.com, 29 Apr. 2026
Intellia's treatment, meanwhile, makes the edits inside the body, or in vivo.
—Angelica Peebles, CNBC, 27 Apr. 2026
See All Example Sentences for in vivo
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Elaine Chen, STAT, 3 June 2026
The scientific community is acutely aware of this, and research priorities are now pivoting toward next-generation in vivo gene-editing approaches where the editing machinery is delivered directly into the body to target the hematopoietic stem cells in situ.
—Tanya Lewis, Scientific American, 5 May 2026
The genetic root cause of the disease, edited in place, in vivo, inside a living human body.
—Jon Markman, Forbes.com, 29 Apr. 2026
Intellia's treatment, meanwhile, makes the edits inside the body, or in vivo.
—Angelica Peebles, CNBC, 27 Apr. 2026
See All Example Sentences for in vivo
Cite this Entry
“In vivo.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/in%20vivo. Accessed 13 Jun. 2026.
Copy CitationKids Definition
in vivo
adverb or adjective
in vi·vo
in-ˈvē-(ˌ)vō
-ˈwē-(ˌ)wō
: inside the living body of a plant or animal
in vivo activity
Etymology
Latin, literally, "in the living"
Medical Definition
in vivo
adverb or adjective
in vi·vo
in-ˈvē-(ˌ)vō
1
: in the living body of a plant or animal
in vivo synthesis of DNA
microorganisms are not ordinarily destroyed in vivo{/qi} by bacteriostatic drugs—The Journal of the American Medical Association
The Journal of the American Medical Association2
: in a real-life situation
observing a patient's behavior in vivo
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