demented

adjective

1. crazy; insane; mad.
2. affected with dementia.

verb (used with object) Obsolete.

1. to make mad or insane.

adjective

1. mad; insane

verb

1. (intr) to deteriorate mentally, esp because of old age
2. (tr) rare to drive mad; make insane

adj.

1640s, from obsolete dement “drive mad.”

v.

1540s, “to drive mad,” probably from Middle French démenter, from Late Latin dementare “to drive out of one’s mind,” from phrase de mente (a less technical term than insanitas), from de + mente, ablative of mens mind” (see mind (n.)).

adj.

1. Mentally ill; insane.
2. Suffering from dementia.