Anglicized spelling of Síle, the Irish Gaelic form of Cecily. This name has become so common and widespread that it is hardly felt to be Irish any longer. In Australia since the 19th century it has been a slang generic term for any woman.
German: from Middle High German bischof, Middle Low German bischop ‘bishop’, probably applied as a nickname for someone with a pompous manner or as a metonymic occupational name for someone in the service of a bishop. See also Bishop.