An aspergillum (less commonly, aspergilium or aspergil) is a liturgical implement used to sprinkle holy water. It comes in two common forms: a brush that is dipped in the water and shaken, and a silver ball on a stick. Some have sponges or internal reservoirs that dispense holy water when shaken, while others must periodically be dipped in an aspersorium (holy water bucket, known to art historians as a situla).
An aspergillum is used in Roman Catholic, Lutheran and Anglican ceremonies, including the Rite of Baptism and during the Easter Season. In addition, a priest will use the aspergillum to bless the candles during Candlemas services and the palms during Palm Sunday Mass. At a requiem, if a coffin is present, the priest will sprinkle holy water on the coffin. The aspergillum can be used in other manners where sprinkling of holy water is appropriate, as in a house blessing, in which the priest might bless the entry to the home. The name derives from the Latin verb aspergere 'to sprinkle'.
The form of the aspergillum differs in the Eastern Orthodox Church. In the Greek Orthodox Church the aspergillum (randistirion) is in the form of a standing vessel with a tapering lid. The top of the lid has holes in it from which the agiasmos (holy water) is sprinkled. In the Russian Orthodox Church the aspergillum is in the form of a whisk made of cloth or hair. Sometimes, sprigs of basil are used to sprinkle holy water. In some of the Oriental Orthodox Churches, no aspergillum is used, but the priest will pour holy water into the palm of his right hand and throw it on the faithful.
An aspergillum is also used in other religions, including Balinese Shaivism (Hinduism).