retardation

noun

1
: an act or instance of retarding
2
: the extent to which something is retarded
3
: a musical suspension
specifically : one that resolves upward
4
a(1)
: an abnormal slowness of thought or action
psychomotor retardation
(2)
now usually offensive : intellectual disability
b
: slowness in development or progress
fetal growth retardation

Examples of retardation in a Sentence

The child suffered severe mental retardation. The chemical induced a retardation of cell growth.
Recent Examples on the Web
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The degree of retardation is usually mild, but can be moderate to severe. Mark Cohen, Discover Magazine, 4 Apr. 2012 The criteria were: episodes that last no longer than 2 months, and that do not include suicidal feelings, psychotic symptoms, psychomotor retardation, or feelings of worthlessness. Neuroskeptic, Discover Magazine, 15 Mar. 2013

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of retardation was in the 15th century

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Cite this Entry

“Retardation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/retardation. Accessed 27 Feb. 2025.

Kids Definition

retardation

noun
1
: an act or instance of retarding
2
: the extent to which something is retarded
3
usually offensive : intellectual disability

Medical Definition

1
a
: an abnormal slowness of thought or action
psychomotor retardation
b
now usually offensive : intellectual disability
2
: slowness in development or progress
fetal growth retardation

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