reactive

adjective
re·​ac·​tive | \ rē-ˈak-tiv How to pronounce reactive (audio) \

Definition of reactive

1 : of, relating to, or marked by reaction or reactance
2a : readily responsive to a stimulus
b : occurring as a result of stress or emotional upset reactive depression

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Other Words from reactive

reactively adverb
reactiveness noun
reactivity \ (ˌ)rē-​ˌak-​ˈti-​və-​tē How to pronounce reactivity (audio) \ noun

Examples of reactive in a Sentence

The government's response to the problem was reactive rather than proactive.

Recent Examples on the Web

And every part of the body has advantages and disadvantages: The immune system is crucial but can be too reactive, leading to autoimmune diseases such as lupus or rheumatoid arthritis. David P. Barash, WSJ, "‘Good Reasons for Bad Feelings’ Review: Suffering’s Silver Lining," 13 Feb. 2019 But these founders hope streamlining the process of getting them will help women move from being reactive to proactive about fertility. Macaela Mackenzie, Glamour, "Do You Need a Fertility Test—Even If You’re Not Trying to Get Pregnant?," 13 Dec. 2018 In the thinner air, controls become too reactive and unpredictable for a human being to manage. Jacqueline Detwiler, Popular Mechanics, "Inside the Jet Propulsion Laboratory: NASA's Crazy, Kooky, Legendary Research Facility," 3 Nov. 2016 But according to Lorenzo Kristov, the rise of new energy technologies should occasion a step back and a fresh, holistic perspective — not just a reactive scramble on policy. David Roberts, Vox, "Clean energy technologies threaten to overwhelm the grid. Here’s how it can adapt.," 30 Nov. 2018 The brine water that has been accumulating for millennia under the Atacama is lithium-rich, and companies pump it out and send the brine to evaporation ponds where heat extracts the water and leaves the reactive alkali metal behind. Megan Geuss, Ars Technica, "Lithium giants feud over competition, brine in Chile’s Atacama Desert," 21 Oct. 2018 For instance, Army developers explain that equipping the Bradley with new suspension, reactive armor tiles and APS can increase the vehicle weight by as much as 3,000-pounds. Kris Osborn, Fox News, "Army makes massive Bradley buy - up to 473 vehicles to prep for major power war," 27 June 2018 My characteristically reactive skin was especially red and inflamed, even though dermaplaning doesn't usually cause irritation on most skin types. Jessica Defino, Marie Claire, "I Got My Face Shaved With a Scalpel in the Name of Smooth Skin," 11 Sep. 2018 Her actions are entirely reactive throughout the first season of the show. Noah Berlatsky, The Verge, "Netflix’s Disenchantment suggests the messy future of princess stories," 22 Aug. 2018

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

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First Known Use of reactive

1717, in the meaning defined at sense 1

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Statistics for reactive

Last Updated

23 Mar 2019

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Time Traveler for reactive

The first known use of reactive was in 1717

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More Definitions for reactive

reactive

adjective

English Language Learners 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

reactive

adjective
re·​ac·​tive | \ rē-ˈak-tiv How to pronounce reactive (audio) \

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

More from Merriam-Webster on reactive

Rhyming Dictionary: Words that rhyme with reactive

Britannica English: Translation of reactive for Arabic Speakers

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