Emily Dickinson Lexicon

MAS'SA-CER, or MAS'SA-CRE, n. [massaker; Fr. massacre; Arm. maçzaer; It. mazzicare, to beat, from mazza, a club, a mace. So smite in English signifies to kill, as well as to beat.]

1. The murder of an individual, or the slaughter of numbers of human beings, with circumstances of cruelty; the indiscriminate killing of human beings, without authority or necessity, and without forms civil or military. It differs from assassination, which is a private killing. It differs from carnage, which is rather the effect of slaughter than slaughter itself, and is applied to the authorized destruction of men in battle, or other great destruction of lives by violence. Massacre is sometimes called butchery, from its resemblance to the killing of cattle. If a soldier kills a man in battle in his own defense, it is a lawful act; it is killing, and it is slaughter, but it is not a massacre. Whereas, if a soldier kills an enemy after he has surrendered, it is massacre, a killing without necessity, often without authority, contrary to the usages of nations, and of course with cruelty. The practice of killing prisoners, even when authorized by the commander, is properly massacre; as the authority given proceeds from cruelty. We have all heard of the massacre of the Protestants in France, in the reign of Charles IX.; and frequent instances of barbarous massacre occur in the war between the Turks and Greeks.
2. Murder. Shak.