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

Keep scrolling for more

Other Words from reactive

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 To prepare the shrimp: Put the shrimp in a non-reactive bowl and add enough lime juice to barely cover., "Recipes for a seasonal bounty: Starters," 18 Sep. 2020 But the reactive nature of the moves raises questions. Adam Marcus, Wired, "Science Journals Are Purging Racist, Sexist Work. Finally," 17 Sep. 2020 Facebook's stance with content by and large tends to be reactive, not proactive. Kate Cox, Ars Technica, "Facebook’s plan to prevent election misinformation: Allowing it, mostly," 3 Sep. 2020 And unlike other schemes for drawing excess CO2 from the atmosphere, these reactive rocks can both capture the gas and store it, locked away permanently in a solid mineral. Robert F. Service, Science | AAAS, "Industrial waste can turn planet-warming carbon dioxide into stone," 3 Sep. 2020 However, salicylic acid is still an exfoliant, and may not be doable if your skin is really reactive or sensitive. Deanna Pai, Glamour, "How to Get Rid of Body Acne, According to Derms," 18 Aug. 2020 Because of childhood neglect, Warner said, Dale suffers from fetal alcohol syndrome and reactive attachment disorder. Special To The Oregonian/oregonlive, oregonlive, "Juvenile justice data shows drop in child defendants sent to adult court," 7 Sep. 2020 That works from a chemical perspective, as long as the reactive lithium is properly protected. John Timmer, Ars Technica, "Could “disordered rock salts” bring order to next-gen lithium batteries?," 4 Sep. 2020 Troitino, the Miami prison guard, said the virus has spread so efficiently through federal facilities because of inconsistent protocols that are almost always reactive rather than preventive. Washington Post, "Prisoners and guards agree about federal coronavirus response: ‘We do not feel safe’," 24 Aug. 2020

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.

See More

First Known Use of reactive

1717, in the meaning defined at sense 1

Keep scrolling for more

Learn More about reactive

Time Traveler for reactive

Time Traveler

The first known use of reactive was in 1717

See more words from the same year

Statistics for reactive

Last Updated

24 Sep 2020

Cite this Entry

“Reactive.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2020.

Keep scrolling for more

More Definitions for reactive


How to pronounce reactive (audio)

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


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

Thesaurus: All synonyms and antonyms for reactive

Britannica English: Translation of reactive for Arabic Speakers

Comments on reactive

What made you want to look up reactive? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Homophone Quiz

  • three bears two of them look like theyre whispering to a third bear who looks chuffed to be the center of attention
  • In order to judge how people felt, the senator's office hired a firm to take a ______.
Spell It

Can you spell these 10 commonly misspelled words?

Add Diction

Test Your Knowledge - and learn some interesting things along the way.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!