Duplicity (noun)

The state or quality of being twofold; double-dealing; hypocrisy; insincerity; deceit.

Origin:

Late 15th century: from french duplicité or latin duplicitas, from duplex, duplic- "double".

Examples:

1. She accused him of duplicity, saying he had lied to her.
2. The duplicity of his actions was finally revealed.
3. The political campaign was marred by accusations of duplicity.
4. The duplicity of his words made it hard to trust him.
5. His duplicity was exposed when he was caught in a lie.