fidelity
The definition for fidelity is "State of being faithful." Used in a sentence: Unlike her fickle friend Benji, May Belle was known for her fidelity.
plaudits
The definition for plaudits is "Enthusiastic approval." Used in a sentence: Allison's painting met with plaudits from the critics, who had dismissed her earlier work.
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.
serenity
The definition for serenity is "Calmness." Used in a sentence: The serenity of the glassy sea soothed the sailors after the big storm.
turpitude
The definition for turpitude is "Essential baseness, depravity." Used in a sentence: The turpitude of the villain in the movie offended most audiences.