reactivity

noun re·ac·tiv·i·ty \ (ˌ)rē-ˌak-ˈti-və-tē \
|Updated on: 12 Aug 2018

Definition of reactivity

: 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
  • Abnormal 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

Recent Examples of reactivity from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reactivity.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of reactivity

1832

in the meaning defined above

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Medical Dictionary

reactivity

noun re·ac·tiv·i·ty \ (ˌ)rē-ˌak-ˈtiv-ət-ē \

medical Definition of reactivity

plural reactivities
: the quality or state of being reactive
  • skin reactivity
  • emotional reactivity

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