What is Homicide Per Infortunium?

Legal Definition
Homicide by misfortune, or accidental homicide ; as where a man doing a lawful act, without any intention of hurt, unfortunately kills another; a species of excusable homicide. 4 Bl. Comm. 182; 4 Steph. Comm. 101.
-- Black's Law Dictionary
Legal Definition
Where a man doing a lawful act, without intention of hurt, unfortunately kills another.
-- Black's Law Dictionary
Legal Definition
-- Ballentine's Law Dictionary