A canoness is a member of a religious community of women living a simple life. Many communities observe the monastic Rule of St. Augustine. The name corresponds to the male equivalent, a canon, though some women may use the title canon and not canoness similar to the way actor is used rather than actress, e.g. Sarah Foot. The origin and Rule are common to both. As with the canons, there are two types: canonesses regular, who follow the Augustinian Rule, and secular canonesses, who follow no monastic Rule of Life.

Canon is a Christian title usually used to refer to a member of certain bodies in subject to an ecclesiastical rule.