An ethnic group, or an ethnicity, is a category of people who identify with each other based on similarities such as common ancestry, language, society, culture or nation. Ethnicity is often an inherited status based on the society in which one lives. Membership of an ethnic group tends to be defined by a shared cultural heritage, ancestry, origin myth, history, homeland, language or dialect, symbolic systems such as religion, mythology and ritual, cuisine, dressing style, art, and physical appearance.
Ethnic groups, derived from the same historical founder population, often continue to speak related languages and share a similar gene pool. By way of language shift, acculturation, adoption and religious conversion, it is sometimes possible for individuals or groups to leave one ethnic group and become part of another (except for ethnic groups emphasizing racial purity as a key membership criterion).
Ethnicity is often used synonymously with ambiguous terms such as nation or people. In English, it can also have the connotation of something exotic (cf. "White ethnic", "ethnic restaurant", etc.), generally related to cultures of more recent immigrants, who arrived after the founding population of an area was established.