Simple Definition of reactive
: done in response to a problem or situation : reacting to problems when they occur instead of doing something to prevent them
chemistry : tending to change into something else when mixed with another substance
Examples of reactive
The government's response to the problem was reactive rather than proactive.
First Known Use of reactive
Medical Definition of reactive
1a: of, relating to, or marked by reaction <reactive symptoms> <a reactive process>b: capable of reacting chemically <highly reactive materials>
2a: readily responsive to a stimulus <the skin of the geriatric is less reactive than that of younger persons—Louis Tuft>b: occurring as a result of stress or emotional upset especially from factors outside the organism <reactive depression>
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