untouchability

Untouchability is a form of social institution that legitimises and enforces practices that are discriminatory, humiliating, exclusionary and exploitative against people belonging to certain social groups. Untouchability also refers to the condition of belonging to such groups, members of whom are historically called untouchables, outcastes, or archaically pariahs. Although comparable forms of discrimination are found all over the world, untouchability involving the caste system is largely unique to South Asia.

The term is most commonly associated with treatment of the Dalit communities in the Indian subcontinent who were considered "polluting". The term has also been used to refer to other groups, including the Burakumin of Japan, the Baekjeong of Korea, and the Ragyabpa of Tibet, as well as the Romani people and Cagot in Europe, and the Al-Akhdam in Yemen. Traditionally, the groups characterized as untouchable were those whose occupations and habits of life involved ritually "polluting" activities, such as pursuing a career based on killing (e.g. fishermen) or engaging in common contact with others' feces or sweat (e.g. manual scavengers, sweepers and washermen).