Compos
/ˈkɒm.pɒs/noun
Mentally competent or sane, chiefly used in the phrase “compos mentis.”
Did you know?In legal Latin, “compos mentis” literally described someone who possessed command of their mind, while its opposite, “non compos mentis,” became a formal designation of mental incapacity.
Etymological Timeline
Proto-Indo-European
PIE
*pótis
“Master, lord, or one who possesses power”
Ancient Sanskrit
Sanskrit
páti
“Lord, master, or husband; a related Indo-European form”
Archaic Latin
Latin
potis
“Able, capable, powerful, or in possession of something”
Classical Latin
Latin
compos
“Having mastery of or being capable of something; from com- (“together, completely”) plus potis”
Classical Latin
Latin
compos mentis
“Master of one’s mind; mentally sound”
16th Century
English
compos mentis
“Sane or mentally competent, especially in legal and formal language”
Modern English
English
compos
“Sane or mentally competent, chiefly preserved in the phrase “compos mentis””