retardation

noun

ˌrē-ˌtär-ˈdā-shən How to pronounce retardation (audio)
Definition of retardationnext
as in deceleration
a usually gradual decrease in the pace or level of activity of something scientists discovered that they could achieve the retardation of light if they shined it through a variety of substances

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

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.
Recent Examples of retardation The Everrati's left pedal operates pads on discs in the normal fashion, but the motors also give powerful regenerative retardation when the accelerator is lifted. — Mike Duff, Car and Driver, 18 June 2021 The policy of retardation of submarine technology ended right after the beginning of the Anglo-German naval race (marked by the German Naval Laws of 1898 and 1900). — chicagotribune.com, 28 July 2017 At the end Austen had psychomotor retardation and could barely move. — Rene Chun, Los Angeles Magazine, 19 June 2017 The degree of retardation is usually mild, but can be moderate to severe. — Mark Cohen, Discover Magazine, 4 Apr. 2012
Recent Examples of Synonyms for retardation
  1. deceleration
  2. decline
  3. slowdown
  4. braking
  5. drop
  6. slump
Noun
  • Over time, without regular use, the back of the body can lose its functional capacity for deceleration, which is when chronic knee pain generally starts to show up.
    — Dana Santas, CNN Money, 20 Aug. 2026
  • But Delapierre was flung forwards violently by the rapid deceleration and suffered a nasty face-plant into the cockpit.
    — Andrew Rice, New York Times, 20 Aug. 2026
Definition of deceleration
Noun
  • Larger coupon payments now provide a cushion against further price declines, unlike the low-yield environment earlier this decade.
    — Lee Ying Shan, CNBC, 3 Sep. 2026
  • Later, Hammer filmed her body’s visible decline from a long battle with cancer, concluding with her death in 2019 at age 79.
    — Rachel Handler, Vulture, 2 Sep. 2026
Definition of decline
Noun
  • Though job creation held positive, August was the smallest gain since January and reflective of a broader slowdown in the labor market.
    — Jeff Cox, CNBC, 2 Sep. 2026
  • What remains of the rock by this stage shrinks rapidly, also slowing significantly, with this slowdown occurring faster if the rock has fragmented more successfully.
    — Robert Lea, Space.com, 1 Sep. 2026
Definition of slowdown
Noun
  • This comprises five customizable ride modes for the 805 RX, plus reverse, allowing riders to adjust characteristics including power delivery, traction control and regenerative braking.
    — New Atlas, New Atlas, 2 Sep. 2026
  • The vehicle will have regenerative braking that is commonplace on most fully electric cars.
    — Keith Laing, USA Today, 2 Sep. 2026
Definition of braking
Noun
  • The surprise drop kicked off a 60-day countdown for the re-issue.
    — Caché McClay, USA Today, 28 Aug. 2026
  • Smooth it through damp hair before styling or use a few drops on dry lengths for an extra hit of shine and polish.
    — Christa Joanna Lee, Allure, 28 Aug. 2026
Definition of drop
Noun
  • Growth in the world's second-largest economy slowed to multi-year lows in the second quarter, weighed down by tepid domestic demand and a prolonged real estate slump.
    — Anniek Bao, CNBC, 3 Sep. 2026
  • The country is more vulnerable to an oil slump than many other producers, making its defense of prices and preservation of OPEC’s relevance a priority.
    — Wael Mahdi, semafor.com, 3 Sep. 2026
Definition of slump

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retardant
retardation
retardations
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Cite this Entry

“Retardation.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/retardation. Accessed 5 Sep. 2026.

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More from Merriam-Webster on retardation

Britannica.com: Encyclopedia article about retardation

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