A Zemindar, sometimes spelt zamindar, is a government revenue collector responsible for collecting taxes in a given area.
Zameen = Land (urdu word) dar = owner. 
One holding land on which he pays revenue to the government direct and not to any intermediate superior. In Bengal proper the zemindars hold generally considerable tracts of land, on a permanent settlement of the amount to be paid to the Government. Zemindars then leased out land to farmers and made a living.