noun
a chronic or persistent disorder of the mental processes caused by brain disease or injury and marked by memory disorders, personality changes, and impaired reasoning
-
Dementia is a neurocognitive disorder characterized by a decline in cognitive function.
-
My grandma has dementia and sometimes she forgets who I am.
-
My memory is so bad, I feel like I have early-onset dementia.
-
The company's financial troubles are a sign of organizational dementia.