What is "oprichnina"

The oprichnina (, ) was a state policy implemented by Tsar Ivan the Terrible in Russia between 1565 and 1572. The policy included institution of secret police, mass repressions, public executions, and confiscation of land from Russian aristocrats. The six thousand political police were called oprichniki, and the term oprichnina also applies to the secret police organization, to the corresponding period of Russian history, and to the territory in which, during that period, the Tsar ruled directly and in which his oprichniki operated.

The term oprichnina, which Ivan coined for this policy, derives from the Russian word oprich (, apart from, except).