What does duplicity mean?
Duplicity refers to deliberate deceitfulness — the practice of presenting one appearance to the world while concealing another intention beneath it. A person guilty of duplicity says one thing and does another, often maintaining a trustworthy facade over a sustained period. The word derives from the Latin duplex, meaning 'twofold', so at its root it captures the idea of doubleness: two faces, two agendas, one person. Today it is used almost exclusively as a term of condemnation, appearing frequently in discussions of politics, diplomacy, business, and personal relationships where hidden motives have been exposed. Its register is formal to literary; in everyday conversation, speakers are more likely to say someone is 'two-faced' or 'deceitful'. Closely related is the adjective duplicitous, describing behaviour marked by such deception. Because it names a specific kind of dishonesty — calculated rather than impulsive — duplicity remains a precise and forceful choice when the charge is not merely lying but living a lie.
Deceitfulness or two-facedness; deliberate concealment of one's true intentions behind a false appearance.
"Years of duplicity came to light when investigators uncovered his second set of accounts."
(Law) The fault of charging a single offence in more than one count of an indictment.
"The defence moved to quash the count on the grounds of duplicity."
A technical legal sense, far less common than the general sense of deceitfulness.
Rare; usually treated as an uncountable noun. The plural appears occasionally in literary contexts referring to repeated instances of deceptive behaviour.
"The biography catalogued the small duplicities that had punctuated the statesman's public life."
Duplicity literally means 'doubleness' — the word itself is a confession that a deceiver lives two lives.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of duplicity
Duplicity comes from the Latin duplicitas ('doubleness'), derived from duplex, meaning 'twofold' or 'double', itself formed from duo ('two') and -plex ('fold'). The word entered English in the early 15th century with a neutral sense of twofoldness, but by the 17th century it had developed its dominant modern sense of deliberate double-dealing. It shares its root with words such as duplicate, duplex, diploma (originally a folded document), and perplex.
Related word forms
How duplicity is actually used
Duplicity carries an unambiguously negative connotation and belongs chiefly to formal or literary registers; in casual speech, words like 'lying' or 'being two-faced' are more common. It implies sustained or systematic deception rather than a single lie. The plural 'duplicities' exists but is rare.
Easily confused with duplicity
Duplication means the act of copying something, whereas duplicity means deceitfulness — despite their shared Latin root meaning 'twofold'.