hairshirt

A garment of coarse cloth made in Cilicia from goat’s hair and worn in the form of a shirt or girdle by way of penance and mortification; probably the same as the scriptural sackcloth, or haircloth in Judith 9. In use from the early ages of Christianity, even among lay people, it was adopted by many religious orders in the Middle Ages and worn by penitents on Ash Wednesday. At present, Carthusians and Carmelites wear it by rule, others as a matter of custom or voluntary mortification.