adversary
The definition for adversary is "One who opposes or resists." Used in a sentence: Franklin hoped to defeat his adversary in the afternoon's tennis match.
corrective
The definition for corrective is "Intended to correct." Used in a sentence: The school decided to take corrective measures to prevent truancy.
implausible
The definition for implausible is "Unbelievable." Used in a sentence: Claudia's implausible excuse failed to convince her teacher.
solace
The definition for solace is "Source of consolation." Used in a sentence: Parents' weekend was a solace to Marjorie, whose beloved daughter had left for college.
unscrupulous
The definition for unscrupulous is "Lacking principles." Used in a sentence: The unscrupulous salesman was fired for lying to his customers.