Lustration is, literally, "a sacrifice, or ceremony, by which cities, fields, armies, or people, defiled by crimes, pestilence, or other cause of uncleanness, were purified". During the period after the fall of the various European Communist states in 1989–1991, the term came to refer to the policy of limiting participation of former communists in the successor governments or even in civil service positions.

References

• The quoted, old definition given here can be found in the 1904 (Merriam) Webster's International Dictionary of the English Language and is public domain.