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
The pup named Relic arrived at the East Bay SPCA in Oakland, California with recognizable signs of shelter stress, including reactivity to humans and animals, according to the shelter.
—Saman Shafiq, USA TODAY, 19 Feb. 2025
James Lloyd, a psychotherapist based in Ireland, told Newsweek that unresolved childhood wounds can lead to anxious attachment styles, difficulty trusting others, and heightened emotional reactivity in relationships.
—Matt Robison, Newsweek, 18 Feb. 2025
For that reason, Levy explains that owners must figure out the type of reactivity their dog is showing, and the history behind it.
—Yaakov Katz, Newsweek, 7 Feb. 2025
But leaders can either amplify the stress or tamp it down based on their own levels of reactivity.
—Shani Harmon, Forbes, 23 Jan. 2025
See all Example Sentences for reactivity 
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Saman Shafiq, USA TODAY, 19 Feb. 2025
James Lloyd, a psychotherapist based in Ireland, told Newsweek that unresolved childhood wounds can lead to anxious attachment styles, difficulty trusting others, and heightened emotional reactivity in relationships.
—Matt Robison, Newsweek, 18 Feb. 2025
For that reason, Levy explains that owners must figure out the type of reactivity their dog is showing, and the history behind it.
—Yaakov Katz, Newsweek, 7 Feb. 2025
But leaders can either amplify the stress or tamp it down based on their own levels of reactivity.
—Shani Harmon, Forbes, 23 Jan. 2025
See all Example Sentences for reactivity
Dictionary Entries Near reactivity
Cite this Entry
“Reactivity.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactivity. Accessed 23 Feb. 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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