The definition for duplicity is "Deceptive thought, speech, or action." Used in a sentence: The life of an undercover detective is filed with necessary duplicity.

The definition for epistolary is "Contained or carried on in letters." Used in a sentence: The shoebox filled with letters was the ony remains of Ming's epistolary friendship with Emile.

The definition for hedonism is "Belief that pleasure is the sole aim of life." Used in a sentence: The hedonism of the emperoro, who spent all his time giving parties, caused his downfall.

The definition for incidental is "Minor." Used in a sentence: The accountant advised Justine not to report her incidental expenses.

The definition for inviolable is "Secure from assault of trespass." Used in a sentence: Situated on a mountain, with sixteen–foot walls, the castle was inviolable.