mental deficiency
noun
: a deficiency in cognitive functioning
specifically
: intellectual disability
Examples of mental deficiency in a Sentence
Recent Examples on the Web
In closing arguments, assistant prosecuting attorneys Spencer Curtis and Robert Sanders slammed testimony from mental health experts who explained Rocha’s mental deficiencies.
—
Pj Green, Kansas City Star, 7 Oct. 2025
Jose Mosqueda said his son, who was last seen about an hour earlier, had a mental deficiency, according to the statement, but no documents were provided to back up these claims.
—Holmes Lybrand, CNN Money, 7 July 2025
Rubella is typically mild in adults and children but can cause serious birth defects in pregnant women, including deafness, cataracts, heart defects, mental deficiency and liver or spleen damage, according to the Texas Department of State Health Services.
—Brandi D. Addison, Austin American Statesman, 3 Mar. 2025
Now that White's execution has been scheduled again, his attorneys are continuing arguments that police took advantage of White's mental deficiencies to elicit a confession without an attorney present.
—Alexis Simmerman, Austin American-Statesman, 1 Oct. 2024
Now that White's execution has been scheduled again, his attorneys are continuing arguments that police took advantage of White's mental deficiencies to elicit a confession without an attorney present.
—Amanda Lee Myers, USA TODAY, 30 Sep. 2024
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
Defense counsel must explain how factors like an abusive upbringing, mental deficiencies, or personal tragedy led their client to commit a terrible crime.
—Ian Millhiser, Vox, 7 Dec. 2018
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Pj Green, Kansas City Star, 7 Oct. 2025
Jose Mosqueda said his son, who was last seen about an hour earlier, had a mental deficiency, according to the statement, but no documents were provided to back up these claims.
—Holmes Lybrand, CNN Money, 7 July 2025
Rubella is typically mild in adults and children but can cause serious birth defects in pregnant women, including deafness, cataracts, heart defects, mental deficiency and liver or spleen damage, according to the Texas Department of State Health Services.
—Brandi D. Addison, Austin American Statesman, 3 Mar. 2025
Now that White's execution has been scheduled again, his attorneys are continuing arguments that police took advantage of White's mental deficiencies to elicit a confession without an attorney present.
—Alexis Simmerman, Austin American-Statesman, 1 Oct. 2024
Now that White's execution has been scheduled again, his attorneys are continuing arguments that police took advantage of White's mental deficiencies to elicit a confession without an attorney present.
—Amanda Lee Myers, USA TODAY, 30 Sep. 2024
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
Defense counsel must explain how factors like an abusive upbringing, mental deficiencies, or personal tragedy led their client to commit a terrible crime.
—Ian Millhiser, Vox, 7 Dec. 2018
Cite this Entry
“Mental deficiency.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mental%20deficiency. Accessed 31 Oct. 2025.
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