Perfidy

Read as \PUR-fi-dee\ and is a form of deception, betrayal of trust, an act of deliberate betrayal; treachery

In the context of war, perfidy is a form of deception, in which one side promises to act in good faith (by raising a flag of surrender) with intention of breaking that promise once the enemy has exposed himself (by coming out of cover in order to capture the surrendering forces). Source:google define

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