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reactive

[ree-ak-tiv]
See more synonyms for reactive on Thesaurus.com
adjective
  1. tending to react.
  2. pertaining to or characterized by reaction.
  3. Electricity. pertaining to or characterized by reactance.
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Origin of reactive

First recorded in 1705–15; react + -ive
Related formsre·ac·tive·ly, adverbre·ac·tive·ness, nounan·ti·re·ac·tive, adjectivehy·per·re·ac·tive, adjectivenon·re·ac·tive, adjectiveo·ver·re·ac·tive, adjectiveun·re·ac·tive, adjective
Can be confusedproactive reactionary reactive
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for reactive

sympathetic, sensible, conscious, susceptible, receptive, compassionate, aware, sensitive, active, reactive, tricky, precise, tense, keen, nervous, touchy, perceptive, unstable, delicate, responsive

Examples from the Web for reactive

Contemporary Examples of reactive

Historical Examples of reactive

  • They rise and fall together; they are reactive, one upon the other.

  • Succedaneum for Chrysarobin; very active reducer or "reactive."

    Merck's 1899 Manual

    Merck & Co.

  • The bandolero was languishing in the third reactive stage of malignant cholera.

    The Wolf Cub

    Patrick Casey

  • But they had been replaced by an uncontrollable, reactive nausea.

    Spillthrough

    Daniel F. Galouye

  • But there are many possible tracer rays not reactive to a screen such as I was using.

    Skylark Three

    Edward Elmer Smith


British Dictionary definitions for reactive

reactive

adjective
  1. readily partaking in chemical reactionssodium is a reactive metal; free radicals are very reactive
  2. of, concerned with, or having a reactance
  3. responsive to stimulus
  4. (of mental illnesses) precipitated by an external causereactive depression
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Derived Formsreactively, adverbreactivity (ˌriːækˈtɪvɪtɪ) or reactiveness, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for reactive

adj.

1712, from react + -ive. Related: Reactively; reactiveness; reactivity.

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Online Etymology Dictionary, © 2010 Douglas Harper

reactive in Medicine

reactive

(rē-ăktĭv)
adj.
  1. Tending to be responsive or to react to a stimulus.
  2. Characterized by reaction.
  3. Tending to participate readily in chemical reactions.
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The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.