Etymologically
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reaction

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Pronunciation

  • IPA: /riˈæk.ʃᵊn/[1]

Etymology

It is formed from re- and action,[2] on the model of French réaction and older Italian reattione,[2] which are from Medieval Latin reāctiō (“reaction”) (accusative reāctiōnem),[2][3][4] a noun of action formed in Late Latin from the past participle of reagere (“to react”), from re- (“back”) and agere (“to do, perform”).[2][3] It is related to react and act.[2][4]

Earliest recorded meaning

Resistance exerted by a body against the impact of another: 1644 in the OED,[5] and the 1640s in Etymonline, as action in resistance or response to another action or power.[2] Merriam-Webster dates the word to 1585.[3] It was originally a word of physics and dynamics.[2]

Semantic evolution

The influence a thing acted upon exerts in return is from 1771.[5] In chemistry, the mutual action of substances upon each other, it is from 1836,[2][5] and the return of an opposite physical state, as of heat after cold, from 1805.[5] The bodily response to a stimulus is from 1896,[5] and in psychology a measurable response from 1887,[5] with reaction time from 1874.[2] The general sense, a response or feeling caused by an event or statement, is from 1914.[2][5] In politics it means opposition to progress or reform, extreme conservatism.[6][7]

Timeline

  • 1585 – first known use.[3]
  • 1644 – resistance of a body.[5]
  • 1771 – reciprocal influence.[5]
  • 1836 – chemical reaction.[2][5]
  • 1874 – reaction time.[2]
  • 1896 – bodily response to a stimulus.[5]
  • 1914 – a general response.[2][5]

Modern meaning

Noun

  1. A response to a stimulus or event.
  2. A reverse or opposing action.
  3. Opposition to political or social progress; extreme conservatism.
  4. In chemistry, a process in which substances interact to form new ones.
  5. In physics, the equal and opposite force exerted in response to another.
  6. A bodily response, especially an allergic one, to a drug or substance.

Word family

  • reactional
  • reactionally
  • react
  • reactant
  • reactionary
  • reactor
  • act
  • reagent

References

  1. ^ Jones, Daniel (2011), Cambridge English Pronouncing Dictionary, 18th ed., ed. Peter Roach, Jane Setter and John Esling, Cambridge: Cambridge University Press
  2. ^ a b c d e f g h i j k l m Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  3. ^ a b c d Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
  4. ^ a b Pearsall, Judy, ed. (1998), The New Oxford Dictionary of English, Oxford: Clarendon Press
  5. ^ a b c d e f g h i j k l Simpson, J. A.; Weiner, E. S. C., eds. (1989), The Oxford English Dictionary, 2nd ed., Oxford: Clarendon Press
  6. ^ The American Heritage Dictionary of the English Language (1992), 3rd ed., Boston: Houghton Mifflin
  7. ^ Soanes, Catherine; Stevenson, Angus, eds. (2004), Concise Oxford English Dictionary, 11th ed., Oxford: Oxford University Press