Longman Dictionary of Contemporary English - mob

~1 n 1 a large, noisy crowd, especially one that is angry and violent  (a mob of demonstrators | mob rule (=when a mob controls the situation rather than the government or the law)) 2 informal a group of people of the same type  (The usual mob of teenagers were standing on the corner.) 3 the Mob the mafia (=a powerful organization of criminals) 4 the mob old use an insulting expression meaning all the poorest and least educated people in society 5 a mob of sheep/cattle AustrE, NZE a large group of sheep or cattle ~2 v mobbed, mobbing to form a crowd around someone in order to express admiration or to attack them  (The actress was mobbed by doting fans.)