ETYM Latin vigilans, -antis, p. pr. of vigilare to watch, from vigil awake: cf. French vigilant. Related to Vigil.
Attentive to discover and avoid danger, or to provide for safety; wakeful; watchful; circumspect; wary.

Množina: vigilantes

Member of a vigilance committee; SYN. vigilance man.
In US history, originally a member of a “vigilance committee”, a self-appointed group to maintain public order in the absence of organized authority, especially in Western frontier communities.<br /> Early vigilante groups included the “Regulators” in South Carolina in the 1760s and in Pennsylvania 1794 during the Whiskey Rebellion. Many more appeared in the 19th century in frontier towns. Once authorized police forces existed, certain vigilante groups, such as the post-Civil War racist Ku Klux Klan, operated outside the law, often as perpetrators of mob violence such as lynching.

Singular of vigilantes is vigilante.

Množina: vigilantisms

The actions of a vigilance committee in trying to enforce the laws.

In a watchful manner; SYN. watchfully.

Množina: vigilantnesses