mental deficiency

noun

: a deficiency in cognitive functioning
specifically : intellectual disability

Examples of mental deficiency in a Sentence

Recent Examples on the Web Federal authorities supported a sentence of life in prison after medical experts concluded Crusius has serious mental deficiencies. David Nakamura, Washington Post, 28 Dec. 2023 The News & Observer did a fact check of a charge by Rep. Greg Murphy, R-N.C., who repeatedly accused the former vice president of mental deficiency. Doug Stanglin, USA TODAY, 19 July 2020 There doesn’t seem to be any negative neurological signs yet for physical or mental deficiencies. Rania Aniftos, Billboard, 2 Dec. 2019 Look at the real-world results of Donald Trump's erratic behavior, whether through mental deficiency or moral deficiency or some combination thereof. NBC News, 25 Aug. 2019 Then English gave his closing arguments, saying that McCoy was guilty, but only of second-degree murder, because of mental deficiencies. Jon Schuppe, NBC News, 12 Jan. 2018

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mental deficiency.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1820, in the meaning defined above

Time Traveler
The first known use of mental deficiency was in 1820

Dictionary Entries Near mental deficiency

Cite this Entry

“Mental deficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mental%20deficiency. Accessed 24 Apr. 2024.

Medical Definition

mental deficiency

noun
: a deficiency in cognitive functioning
specifically : intellectual disability

Legal Definition

mental deficiency

noun
: failure in intellectual development that is marked by low intelligence or mental retardation and that may result in an inability to function competently in society

More from Merriam-Webster on mental deficiency

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