Deloping was an Irish custom that had grown before the Irish Code duello of discharging one's firearm in the air (usually to one side) when two friends had quarreled and one wished to end the duel without harming his friend. Far too often, this custom resulted in accidents. It was thus forbidden by the Irish a Duello. A code duello is a set of rules for a one-on-one combat, or duel. ... A duel or duel of honour is a formalised type of armed combat in which two individuals participate. ...