The word "paaturi" comes from the Bangla word "paata" or leaf . That said, it becomes crystal clear that "Maacher Paturi" or Fish Paturi is a preparation where the fish is cooked in some sort of a leaf. It being a Bengali recipe. it also becomes more than crystal clear that the said fish has been marinated in a sharp, pungent mustard-y paste of shorshe bata and drizzled with mustard oil.