Akademik

dementia of the aged; results from degeneration of the brain in the absence of cerebrovascular disease

noun [noncount]

medical : a condition that affects the mind of aging people and causes them to be confused, to forget things, etc.

ˌsenile deˈmentia [senile dementia] noun uncountable

a serious mental ↑disorder in old people that causes loss of memory, loss of control of the body, etc.