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 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 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
Recent Examples of Synonyms for retardation
  1. deceleration
  2. decline
  3. slowdown
  4. braking
  5. drop
  6. slump
Noun
  • Match analysis from professional football also suggests around a quarter fewer explosive accelerations and decelerations at altitude than at sea level.
    — Alan McCall, New York Times, 1 July 2026
  • Hamstring strains often occur during sprinting or rapid deceleration, while groin strains are linked to cutting movements and powerful inside-foot kicks.
    — Encyclopedia Britannica, Encyclopedia Britannica, 15 June 2026
Definition of deceleration
Noun
  • Surveys showing a decline in Americans who see democracy as important.
    — Chris Kenning, USA Today, 2 July 2026
  • This decision stems from chronic staffing shortages, crumbling infrastructure, budget constraints, and a substantial decline in the federal inmate population, which peaked in 2013 and has since fallen by nearly 30%.
    — Walter Pavlo, Forbes.com, 1 July 2026
Definition of decline
Noun
  • That puts more pressure on new Fed Chair Kevin Warsh and his colleagues, a dissent-happy bunch over the past year, to consider whether a slowdown in jobs or an uptick in inflation is the bigger risk to the economy.
    — Jake Angelo, semafor.com, 2 July 2026
  • Michelle Monaghan is making midlife look less like a slowdown and more like a second wind.
    — Mara Santilli, Flow Space, 2 July 2026
Definition of slowdown
Noun
  • Tesla has not clarified if its semitruck has an automatic emergency braking system.
    — Los Angeles Times, Los Angeles Times, 2 July 2026
  • The track features long straights and not many braking points to recharge their batteries, just like Austria.
    — Madeline Coleman, New York Times, 1 July 2026
Definition of braking
Noun
  • The patriotic ball drop is scheduled to air at midnight ET on CNN as July 3 turns into July 4 in Times Square.
    — Nicole Fallert, USA Today, 4 July 2026
  • Tesla’s results – which came in above expectations – indicate the company may be recovering after two straight years of annual sales drops and the removal EV tax credits in the US, which has lowered the incentive for prospective American buyers.
    — Chris Isidore, CNN Money, 3 July 2026
Definition of drop
Noun
  • Bregman has been a consistent presence at the plate for the Red Sox as well as the Houston Astros in his career, so the slump is fairly surprising.
    — Peter Chawaga, Forbes.com, 2 July 2026
  • Drake Baldwin snapped an 0-for-36 slump with a single in the seventh.
    — CBS News, CBS News, 1 July 2026
Definition of slump

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retardation
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Cite this Entry

“Retardation.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/retardation. Accessed 8 Jul. 2026.

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More from Merriam-Webster on retardation

Nglish: Translation of retardation for Spanish Speakers

Britannica.com: Encyclopedia article about retardation

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