You call your husband's senior brother simply a brother in-law. There is no difference whether he is a senior brother or a younger brother he remains your brother in-law.
brother in law or their name
Sister-in-Law
what i call my father elder brother's wife
The word for brother in Tamil is "சகோதரன்" (sakodharan).
Your brother would call your husbands sister by her first name. Or, "my (sibling's) sister in law.
You would call your husband's younger brother a brother-in-law.
You can call your husband's elder brother as "Anna" in Tamil.
I will call her niece.
Your brother's wife is your sister-in-law.
brother in law or their name
In Malayalam, elder brother is called "ചേട്ടന്" (chettan).
what i call my father elder brother's wife
what i call my father elder brother's wife