perfidy
UK: /ˈpɜː.fɪ.di/ | US: /ˈpɜːr.fɪ.di/
n. deliberate breach of trust or faith; treachery
n. an act or instance of betrayal
The word "perfidy" originates from Latin perfidia, combining per- (thoroughly) and fides (faith). The root fid appears in words like "fidelity" (faithfulness) and "confide" (to trust). Over time, perfidia evolved to mean "thorough betrayal," emphasizing a complete violation of trust. The suffix -y nominalizes the concept, turning it into an abstract noun. This etymological journey reflects the logical progression from "faith" to its deliberate opposite—treachery.
The spy's perfidy shocked his colleagues, who had trusted him for years.
Political perfidy often leads to public disillusionment.
The treaty was nullified due to the king's perfidy.
Her perfidy in leaking confidential documents ruined her reputation.
History remembers the general's perfidy as a cautionary tale.