Tarafdar (spelling variations: Taraphdar, Taraphder, Tarafder) is a surname found in Bangladesh and the states of West Bengal and Karnataka in India. Historically, the surname originates from Afghanistan, but was brought to Bengal by Afghan settelers . The title was bestowed upon the Local landlords of Bengal.
The Tarafdar maintained all the accounts and handled all the monetary/financial transactions for his land.
The title was a prestigious position, so descendants continued claiming it, and it turned into a surname.
In Bengali it indicates someone who is a joiner of organizations.
It was also a title bestowed by the Ottoman Turks. A ruler of a "Taraf" was a "Tarafdar". It has come to be used as a last name in every country where the Ottomans once had their empire.