From Longman Dictionary of Contemporary Englishringleaderring‧lead‧er /ˈrɪŋˌliːdə $ -ər/ noun [countable] SCCsomeone who leads a group that is doing something illegal or wrong the ringleader of a new international drugs ring► see thesaurus at leader
Examples from the Corpus
ringleader• Dulé survived, however, to be brought to trial as a ringleader, to be an example to others.• The arrested rioters were ultimately released, although the black ringleaders were ordered to leave town.• When twelve deputy sheriffs came to serve warrants for arrest of the black ringleaders, they were ambushed in the grocery store.• The two other ringleaders escaped capture, but many other lesser lights were taken and rather harshly treated.• Three weeks before Bloody Sunday he had recommended shooting selected ringleaders of the youths who regularly rioted in the city.• Shoot the ringleaders, that's what I say.• Detectives are now trying to trace the ringleader of what could be a new international racket.• The ringleaders are facing life in prison.• The ringleader and another man lay on the ground, writhing and screaming. 