Antithesis:
A balancing of two opposite or contrasting words, phrases or clauses.

Example:

"They were, in fact and at last free. And the lives of these old black women were synthesized in their eyes—a puree of tragedy and humor, wickedness and serenity, truth and fantasy.”
—Toni Morrison, The Bluest Eye

Explanation:
This is a great example of antithesis. This quote compares contrasting words multiple times. "tragedy and humor", "wickedness and serenity", and "truth and fantasy". The author uses this to show the reader all of what the women had to endure in her lifetime. The ups and downs, which are best realized when compared next to each other. The author uses this to make the argument as strong and evident as possible.