Ringleader

Noun

 * 1) a leader of a group of people, especially an unofficial group
 * 2) a person who starts and leads a disturbance (such as a riot), a conspiracy, or a criminal gang
 * 3) * The police arrested the ringleaders of the smuggling operation.
 * 4) * (1590): William Shakespeare, King Henry VI, Part 2: A sort of naughty persons, lewdly bent, / Under the countenance and confederacy / Of Lady Eleanor, the protector's wife, / The ringleader and head of all this rout, / Have practis'd dangerously against your state...

Thesaurus
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

Etymology
ring + leader

Translations

 * Basque: taldeburu, buruzagi, gidari


 * German: Anführer, Anführerin


 * German:, Rädelsführerin


 * Manx: ard-veereiltagh