noun. A person who leads others, especially in illicit or informal activities.

noun. One who leads a ring, as of dancers; one who opens a ball.

noun. Hence The leader or chief in any enterprise; particularly, one who leads and incites others to the violation of the law or the recognized rules of society: as, the ringleader in a riot or a mutiny.

noun. The leader of a circle of dancers; hence, the leader of a number of persons acting together; the leader of a herd of animals.

noun. 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.

noun. a leader of a group of people, especially an unofficial group

noun. a person who starts and leads a disturbance (such as a riot), a conspiracy, or a criminal gang

noun. a person who leads (especially in illicit activities)

"They will also come into contact with a traveling carnival which also seeks out people with abilities and whose sinister ringleader is played by new cast member Robert Knepper (Prison Break)."

firebrand  inciter  instigant  instigator  provoker  

citee  ensigne  fraight  instigator  insurrectionist  

Mahdi  agent provocateur  agitator  agitprop  bell cow