The idea of doubleness is at the core of duplicity. Duplicity comes from a Latin word meaning "double" or "twofold," and its original meaning in English has to do with a kind of deception in which you intentionally hide your true feelings or intentions behind false words or actions. If you are being duplicitous there are two yous: the one you're showing and the one you're hiding. And—key to the idea of duplicity—you're hiding that you in order to make people believe something that's not true.
The word is found in many works of literature, including the Bible:
The integrity of the upright guides them, but the unfaithful are destroyed by their duplicity. — Proverbs 11:3 (New International Version)
Even when he sat opposite me in the kitchen, talking, he would turn his head a little toward the clock or the stove and look at me from the side, but with frankness and good nature. This trick did not suggest duplicity or secretiveness…. — Willa Cather, My Antonia, 1918
Arch read it at breakfast the day it came out and again that night. He admired its art but was most, affected, and in fact discomfited, by its unblinking inventory of self-seeking and duplicity. — Tobias Wolff, Old School, 2003
warned her not to trust the duplicitous art dealer
Recent Examples on the WebYears later, Sorvino would direct his own version of the story for Showtime, trading the role of duplicitous 1957 Fillmore High School basketball team member Romano for that of Coach Spinel and delighting Miller.Los Angeles Times, 25 July 2022 Jenkins’s degradation by her duplicitous husband, then her impending illness and death by venereal disease, represented a low point in female victimhood, perfectly timed for the burgeoning #MeToo movement. Armond White, National Review, 6 July 2022 And then there's Babe Bennett (Winona Ryder), a duplicitous reporter who cozies up to the main character under false pretenses — and falls for his small-town charms. Leah Greenblatt, EW.com, 29 June 2022 To many of his new colleagues, Meadows quickly came across as duplicitous and untrustworthy. Susan B. Glasser, The New Yorker, 7 June 2022 Pike's duplicitous performance is a blast to witness, but seeing Marla meet her match is just as gratifying. Gwen Ihnat, EW.com, 13 June 2022 To Raffi, though, Gessen’s Russian rages seem duplicitous. Daniel Engber, The Atlantic, 7 June 2022 As implied earlier, felons, especially the ones who escape from prisons, are extremely clever and duplicitous in nature. Naveen Joshi, Forbes, 2 June 2022 But, those who are in Mike’s immediate social circle have always known his duplicitous nature, and therefore his tentacled approach to business, socio-political activism, and Black financial empowerment is nothing new to them. Jasmine Browley, Essence, 6 May 2022 See More