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.
antidote
The definition for antidote is "Something that relieves or counteracts." Used in a sentence: Veronique found that listening to French music was an antidote for her homesickness.
apathetic
The definition for apathetic is "Showing little or no emotion." Used in a sentence: Carmine was concerned about his usually cheerful brother's apathetic attitude.
nurture
The definition for nurture is "To further the development of." Used in a sentence: Our cat made a nest of blankets to nurture her newborn kittens.
unscrupulous
The definition for unscrupulous is "Lacking principles." Used in a sentence: The unscrupulous salesman was fired for lying to his customers.