reactivity
noun
re·ac·tiv·i·ty
(ˌ)rē-ˌak-ˈti-və-tē 
: the quality or state of being reactive
emotional reactivity
chemical reactivity
If the brain, responding to psychological stress, stimulates the release of cortisol and cortisol suppresses the reactivity of the immune system, then a dormant viral infection may well flare up, or a new one catch hold.—
Matt Ridley
Matt RidleyAbnormal reactivity to light and abnormal pupillary size may be important clues to the presence of cranial injury in the setting of head trauma.—Bradford J. Shingleton
Bradford J. ShingletonExamples of reactivity in a Sentence
Recent Examples on the Web
This enhances the likelihood that subsequent communication will be guided by emotional attunement rather than defensive reactivity.
2.
—Mark Travers, Forbes.com, 12 Apr. 2025
Lazar describes the amygdala as being all about emotional reactivity, particularly fear.
—Avery Hurt, Discover Magazine, 17 Mar. 2025
Diets that protect the immune system can benefit everyone, especially those with a disease rooted in immune reactivity, such as allergic asthma.
—Daniel More, Verywell Health, 25 Mar. 2025
Ultimately, to address the issues of episodic care, reactivity, generalized treatment, and siloed approach, the healthcare system of the future must be continuous, proactive, personalized, and integrative.
—Kyle J. Russell, USA TODAY, 6 Mar. 2025
See All Example Sentences for reactivity
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Mark Travers, Forbes.com, 12 Apr. 2025
Lazar describes the amygdala as being all about emotional reactivity, particularly fear.
—Avery Hurt, Discover Magazine, 17 Mar. 2025
Diets that protect the immune system can benefit everyone, especially those with a disease rooted in immune reactivity, such as allergic asthma.
—Daniel More, Verywell Health, 25 Mar. 2025
Ultimately, to address the issues of episodic care, reactivity, generalized treatment, and siloed approach, the healthcare system of the future must be continuous, proactive, personalized, and integrative.
—Kyle J. Russell, USA TODAY, 6 Mar. 2025
See All Example Sentences for reactivity
Cite this Entry
“Reactivity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactivity. Accessed 29 Apr. 2025.
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reactivity
noun
re·ac·tiv·i·ty
(ˌ)rē-ˌak-ˈtiv-ət-ē
plural reactivities
: the quality or state of being reactive
skin reactivity
emotional reactivity
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