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.

The definition for avian is "Relating to birds." Used in a sentence: The old man affectionately referred to pigeons as his "avian friends."

The definition for corroborate is "To support with evidence." Used in a sentence: "Unless you can corroborate your story, it will not be admissible in court," the attorney told his client.

The definition for mediate is "To come between parties in order to reconcile." Used in a sentence: The diplomatic Henry was able to mediate between the quarreling sisters.

The definition for promote is "To contribute to the growth or prosperity of." Used in a sentence: The promote peace, the diplomat hosted a talk between the warring nations.