Massacre

Webster's Dictionary of the English Language

·noun Murder.

II. Massacre ·noun The killing of a considerable number of human beings under circumstances of atrocity or cruelty, or contrary to the usages of civilized people; as, the massacre on St. Bartholomew's Day.

III. Massacre ·noun To kill in considerable numbers where much resistance can not be made; to kill with indiscriminate violence, without necessity, and contrary to the usages of nations; to Butcher; to Slaughter;

— limited to the killing of human beings.