lustration
nounCeremonial purification; especially, a religious act of purgation or cleansing by the use of water or certain sacrifices or ceremonies, or both, performed among the ancients upon persons, armies, cities, localities, animals, etc.
nounThe act of lustrating or purifying.
nounA sacrifice, or ceremony, by which cities, fields, armies, or people, defiled by crimes, pestilence, or other cause of uncleanness, were purified.
nounA rite of purification, especially washing.
nounThe restoration of credibility to a government by the purging of perpetrators of crimes committed under an earlier regime.