active immunity
noun
: usually long-lasting immunity that is acquired through production of antibodies within the organism in response to the presence of antigens compare passive immunity
Examples of active immunity in a Sentence
Recent Examples on the Web
Rather than using active immunity—where a person’s body produces the antibodies themselves—people would receive an injection of the antibodies to battle the virus.
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Tara Haelle, Scientific American, 23 Sep. 2025
Your active immunity is how your immune system responds to germs by producing its own antibodies.
—Leah Groth, Health, 17 Nov. 2023
But active immunity, achieved with mRNA, means the body can remember how to create the response on its own.
—Hope Reese, Discover Magazine, 23 Dec. 2021
In active immunity, antibodies are generated through exposure to a pathogen or a vaccine.
—Los Angeles Times, 3 Dec. 2020
But passive immunity doesn't last as long as active immunity, and loses effectiveness within a few weeks or months, per the CDC.
—Leah Groth, Health.com, 15 Apr. 2020
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Tara Haelle, Scientific American, 23 Sep. 2025
Your active immunity is how your immune system responds to germs by producing its own antibodies.
—Leah Groth, Health, 17 Nov. 2023
But active immunity, achieved with mRNA, means the body can remember how to create the response on its own.
—Hope Reese, Discover Magazine, 23 Dec. 2021
In active immunity, antibodies are generated through exposure to a pathogen or a vaccine.
—Los Angeles Times, 3 Dec. 2020
But passive immunity doesn't last as long as active immunity, and loses effectiveness within a few weeks or months, per the CDC.
—Leah Groth, Health.com, 15 Apr. 2020
Cite this Entry
“Active immunity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/active%20immunity. Accessed 30 Oct. 2025.
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