the group of British MPs from the Opposition (= the main party opposing the government) who would probably form the Cabinet if their party were in power. Each member of the Shadow Cabinet speaks on behalf of their party on matters for which he or she would be responsible.
SHADOW CABINET
Meaning of SHADOW CABINET in English
Oxford guide to British and American culture English vocabulary. Руководство по британской и американской культуре, Оксфордский английский словарь. 2005