Senile (adjective)

1. Of or relating to old age, especially the stage of old age characterized by physical and mental deterioration.
2. Characterized by or arising from the infirmities of old age.

Origin:

From latin senilis, from senex "old".

Examples:

1. The patient showed signs of senile dementia.
2. He was becoming more and more senile as he aged.
3. The senile patient required constant care.
4. The senile changes in the brain caused memory loss.
5. The nursing home specialized in caring for senile patients.