duplicity
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.
impenitent
The definition for impenitent is "Lacking remorse." Used in a sentence: The impenitent criminal received a harsh penalty, but his remorseful accomplice was released.
incidental
The definition for incidental is "Minor." Used in a sentence: The accountant advised Justine not to report her incidental expenses.
naive
The definition for naive is "Lacking worldy wisdom." Used in a sentence: The naive Simon assumed that everyone was as simple and kind as he was.
ploy
The definition for ploy is "A contrived plan." Used in a sentence: Sarah thought George's ploy of borrowing her notes was a cowardly way to ask her out.