/pɜːrfɪdi/ – Noun
Definition: sự bội tín, sự phản bội, sự xảo trá, sự lừa dối.
A more thorough explanation: Perfidy is a legal term that refers to the act of deliberate deceit or betrayal, especially in the context of violating a trust or commitment. In international law, perfidy is considered a war crime and involves using treacherous tactics to deceive the enemy, such as pretending to surrender and then attacking.
Example: The defendant’s perfidy was evident when he knowingly provided false testimony under oath during the trial.