appalling
The definition for appalling is "Inspiring dismay or disgust." Used in a sentence: Hector found his roommate's habit of leaving his dirty socks on the floor appalling.
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.
opportune
The definition for opportune is "Suitable or convenient." Used in a sentence: Quan stepped onto the platform at the most opportune time, just as the train pulled in.
redouble
The definition for redouble is "To make twice as great." Used in a sentence: As the sun began to set, Brittany redoubled her effort to find the necklace she had dropped in the field.
unscrupulous
The definition for unscrupulous is "Lacking principles." Used in a sentence: The unscrupulous salesman was fired for lying to his customers.