non compos mentis

[nohn kohm-pohs men-tis, non kom-puhs men-tis]

adjective

Latin.

1. not of sound mind; mentally incapable of managing one's affairs (used especially in a legal context).

non compos mentis

/ ˈnɒn ˈkɒmpəs ˈmɛntɪs /

adjective

1. mentally incapable of managing one's own affairs; of unsound mind

non compos mentis

1. A phrase used to describe someone who is out of his or her mind and therefore not legally responsible for his or her actions: “It was determined by the court that the killer was non compos mentis.” From Latin, meaning “not having control of the mind.”

Word History and Origins

Origin of non compos mentis¹

Latin: not in control of one's mind

Example Sentences

Discussing the song, he quickly notes that “nincompoop” is derived from the Latin phrase “non compos mentis” meaning “not of sound mind.”

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The lyrics of Mr. Trump’s recent foreign policy speech may have been non compos mentis but the music featured an authentic lilt.

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The conceit was impractical, to say the least, and most descriptions of the process suggested the auteur might finally have taken a turn toward non compos mentis.

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If anyone proposes another match race between these two super horses,” wrote a reporter after the race, “henceforth, he will be tried in the morning for treason, mutiny, mopery and non compos mentis.'''’

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Some people shammed away this confession, and said he was non compos mentis; and had a mind, it seems, to assume the glory of being hanged for the greatest villain.

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