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

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, "Supreme Court to hear case of lawyer who defied client in murder trial," 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

The first known use of mental deficiency was in 1820

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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

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