non compos mentis

[ nohn kohm-pohs men-tis; English 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). Compare compos mentis ( def ).

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

The case is the same, betwixt a king non compos mentis, and one who is nondum compos mentis; a distracted or an infant-king.

From Project Gutenberg

That either husband or wife is a hopeless lunatic or non compos mentis.

From Project Gutenberg

Sarojini took particular pains to empress it upon me that Chavigny is non compos mentis.

From Project Gutenberg

Now and again would come a suppressed whistle, and then a low humming sound, backed up by a vacant non-compos-mentis smile.

From Project Gutenberg

I made my will this morning, and if it became known that I had refused a fee, I might be deemed non compos mentis.

From Project Gutenberg