mental deficiency


Definition of mental deficiency

: a deficiency in cognitive functioning specifically : intellectual disability

Examples of mental deficiency in a Sentence

Recent Examples on the Web 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 example sentences are selected automatically from various online news sources to reflect current usage of the word 'mental deficiency.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of mental deficiency

1820, in the meaning defined above

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Time Traveler for mental deficiency

Time Traveler

The first known use of mental deficiency was in 1820

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Dictionary Entries Near mental deficiency

mental chemistry

mental deficiency

mental faculties

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Statistics for mental deficiency

Cite this Entry

“Mental deficiency.” Dictionary, Merriam-Webster, Accessed 7 Jul. 2022.

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More Definitions for mental deficiency

mental deficiency


Medical Definition of mental deficiency

: a deficiency in cognitive functioning specifically : intellectual disability

mental deficiency


Legal Definition of mental deficiency

: 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

Thesaurus: All synonyms and antonyms for mental deficiency Encyclopedia article about mental deficiency


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