reactive

adjective

re·​ac·​tive rē-ˈak-tiv How to pronounce reactive (audio)
1
: of, relating to, or marked by reaction or reactance
2
a
: readily responsive to a stimulus
b
: occurring as a result of stress or emotional upset
reactive depression
reactively adverb
reactiveness noun

Examples of reactive in a Sentence

The government's response to the problem was reactive rather than proactive.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Up until this point, their private war had mostly been reactive. Rafaela Bassili, Vulture, 10 Sep. 2025 The Difference Of Agentic AI Traditional AI systems are reactive. Abhishek Singh, Forbes.com, 10 Sep. 2025 Like the smaller distilleries, the whiskey was aged for 12 years in used instead of new barrels, perhaps with the intention of releasing an older expression (the wood is less reactive in used barrels than in new charred oak). Jonah Flicker, Robb Report, 7 Sep. 2025 The process, called phototoxicity, happens when light-reactive chemicals from fragrances and other substances sit on the skin and are exposed to sunlight. Leslie Baumann, Miami Herald, 4 Sep. 2025 See All Example Sentences for reactive

Word History

First Known Use

1717, in the meaning defined at sense 1

Time Traveler
The first known use of reactive was in 1717

Browse Nearby Words

Cite this Entry

“Reactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reactive. Accessed 13 Sep. 2025.

Kids Definition

reactive

adjective
re·​ac·​tive rē-ˈak-tiv How to pronounce reactive (audio)
1
: of or relating to reaction
2
: reacting or tending to react
reactively adverb
reactiveness noun
reactivity noun

Medical Definition

reactive

adjective
re·​ac·​tive rē-ˈak-tiv How to pronounce reactive (audio)
1
a
: of, relating to, or marked by reaction
reactive symptoms
a reactive process
b
: capable of reacting chemically
highly reactive materials
2
a
: readily responsive to a stimulus
the skin of the geriatric is less reactive than that of younger personsLouis Tuft
b
: occurring as a result of stress or emotional upset especially from factors outside the organism
reactive depression

More from Merriam-Webster on reactive

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