Is it permissible to address a man as "O the gray-haired one"?

The student: Some people say, "The gray-haired one has come."

The Shaykh : This is actually a mistake, because this is a form of belittlement. It is a statement that is not problematic... the lowliness of describing him as the gray-haired one... but it appears that among the Bedouins, it is not considered undutifulness.
The student: It is considered, meaning it is an honor.

The Shaykh : Strange.
The student: The gray-haired one is considered

The Shaykh : the elder of the group.
The student: "Abu So-and-so" means one of my brothers; I want to say to him, "O Abu So-and-so."
The Shaykh : The kunyah that he brought up... the one he asked about, because we said the kunyah is less severe than the name. So, I say