(pathology) A progressive decline in cognitive function due to damage or disease in the brain beyond what might be expected from normal aging. Areas particularly affected include memory, attention, judgement, language and problem solving.
Insane or mentally ill.
Madness or insanity.
Suffering from dementia.
Insanity; madness; esp. that form which consists in weakness or total loss of thought and reason; mental imbecility; idiocy.
(informal) Crazy; ridiculous.
‘a demented idea’;
mental deterioration of organic or functional origin
simple past tense and past participle of dement
Dementia manifests as a set of related symptoms, which usually surface when the brain is damaged by injury or disease. The symptoms involve progressive impairments to memory, thinking, and behavior, which negatively impact a person's ability to function and carry out everyday activities.
Insane; mad; of unsound mind.
affected with madness or insanity;
‘a man who had gone mad’;