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."
extol
The definition for extol is "To praise highly." Used in a sentence: The statesman extolled the ambassador who single–handedly negotiated the peace treaty.
placebo
The definition for placebo is "An inactive substance used in medical testing." Used in a sentence: Tom, who had taken the placebo, found that his allergy symptoms did not go away.
repel
The definition for repel is "To resist, reject." Used in a sentence: The soldiers made a massive charge to repel the invaders.