Ringleader

1. (n.) The leader of a circle of dancers; hence, the leader of a number of persons acting together; the leader of a herd of animals.

2. (n.) Opprobriously, a leader of a body of men engaged in the violation of law or in an illegal enterprise, as rioters, mutineers, or the like.

Thesaurus Entries

Mahdi, agent provocateur, agitator, agitprop, bell cow, bell mare, bellwether, born leader, boss, cacique, catalyst, charismatic leader, choirmaster, choragus, conductor, coryphaeus, demagogue, duce, exciter, file leader, firebrand, fomenter, forerunner, fugleman, incendiary, inciter, inflamer, inspired leader, instigator, keynoter, leader, leader of men, man higher up, messiah, mischief-maker, pacemaker, pacesetter, policy maker, precentor, provocateur, provoker, rabble-rouser, rouser, sachem, seditionary, seditionist, standard-bearer, symphonic conductor, torchbearer, troublemaker, urger