An ablution is a washing or a cleaning of oneself, for personal hygiene, or a ritual washing or cleaning associated with religious observance.
The word ablution comes from the Latin abluere, meaning "to wash away." Back in the Middle Ages this term referred to the use of liquids for purification in chemistry; it later took on religious meaning. All the major religions have some rituals of purification. Examples include the washing of the hands or feet, and the cleansing of sacred containers or other objects.