flaw
The definition for flaw is "An imperfection." Used in a sentence: The otherwise perfect diamond had a tiny flaw that reduced its value.
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.
proximity
The definition for proximity is "Closeness." Used in a sentence: The proximity of Tia's house to school meant that she could walk there in five minutes.
prune
The definition for prune is "To reduce by removing excess." Used in a sentence: The candidate pruned his speech so he would not exceed the time limit.
serenity
The definition for serenity is "Calmness." Used in a sentence: The serenity of the glassy sea soothed the sailors after the big storm.