augment
The definition for augment is "To make greater." Used in a sentence: Wanda read the dictionary every night to augment her vocabulary.
avian
The definition for avian is "Relating to birds." Used in a sentence: The old man affectionately referred to pigeons as his "avian friends."
censure
The definition for censure is "To find fault with." Used in a sentence: The critical teacher was quick to censure her students for even small mistakes.
foil
The definition for foil is "One that enhances or underscores by contrast." Used in a sentence: The sweet cookie was a perfect foil to the sour lemon sorbet.
mediate
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.