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.
Sister-in-Law
கொழுந்தனார் (kozhundhanaar) husband's (usually elder) brother.
what i call my father elder brother's wife
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.
In Malayalam, elder brother is called "ചേട്ടന്" (chettan).
I will call her niece.
Your brother's wife is your sister-in-law.
brother in law or their name
The elder brother's wife is called "Bhabhi" in Hindi.
In Hindi, your father's elder brother is called "chacha" (चाचा).
what i call my father elder brother's wife