district of London, so called because it was laid out by four brothers of a family named Adam, from Greek adelphos "brother," literally "from the same womb," from copulative prefix a- "together with" + delphys "womb," perhaps related to dolphin. The district was the site of a popular theater c. 1882-1900, which gave its name to a style of performance.[Adelphia etymology, Adelphia origin, 英语词源]