Duplicity is saying one thing while meaning another. Accused of duplicity, the duplicity of it, sheer duplicity.
The word is built on doubleness, which is exactly the charge: a duplicitous person keeps two accounts running at once. It is a heavier accusation than dishonesty because it implies a settled habit.
1nounduplicitySaying one thing while meaning another.
“When she discovered his duplicity, she realised he had been lying to both of them.”
duplicity is a deceit.
The Latin behind it is double. Duplicity is having two faces and showing you only ever one of them.
hooks ontodouble
Latin duplex means twofold, from duo, two, plus plicare, to fold.
From Latin duplicare (double). Equivalent to duplex + ity.
Etymology from Wiktionary, CC BY-SA