A more thorough explanation:

Senility refers to the mental weakness or impairment that is caused by old age. It is a condition where a person's mental abilities decline due to aging.

In legal terms, a senile person is considered incompetent to enter into a binding contract or to execute a will. This means that they are not capable of making important decisions on their own.

Senile dementia is another term used to describe this condition. It is a type of dementia that affects older people and is characterized by memory loss, confusion, and difficulty in performing daily activities.

For example, an elderly person who forgets their own name or struggles to remember important events from their past may be experiencing senility. Another example is an older person who is unable to manage their finances or make important decisions about their healthcare.

These examples illustrate how senility can affect a person's mental abilities and make it difficult for them to function independently. It is important to provide support and care for elderly individuals who are experiencing senility to ensure that they can maintain their quality of life.