Verbal irony is when a character says something but means something else. Taken literally, the character seems to mean one thing. Actually, they mean to communicate something completely different than what their words literally mean. Verbal irony is different than other kinds of irony because the speaker uses this double meaning intentionally.
In "The Story of An Hour," the first example of verbal irony happens when Josephine is kneeling outside her sister's door, begging her to come out so she can comfort her.
Josephine was kneeling before the closed door with her lips to the keyhole, imploring for admission. "Louise, open the door! I beg; open the door—you will make yourself ill. What are you doing, Louise? For heaven's sake open the door.
"Go away. I am not making myself ill." No, she was drinking in a very elixir of life through that open window.
When Louise says, "I am not making myself ill," she actually means that she has never felt better. She realizes that her sister will not understand the double meaning of her words, but she says it anyway. Her relief and joy at her husband's death evoked a profound sense of freedom inside her. When she says, "I am not making myself ill," it is a statement to herself. In fact, it is possible that what had really been making her ill was her unhappy marriage. At the beginning of the short story, we are told that Louise has heart trouble.
Knowing that Mrs. Mallard was afflicted with a heart trouble, great care was taken to break to her as gently as possible the news of her husband's death.
If her heart trouble was actually caused by the stress of an unhappy marriage, then Louise's statement "I am not making myself ill" is even more ironic, since the relief she feels after she is told of her husband's death is actually making her well.
The next example of verbal irony happens after Brently Mallard returns, alive and well. At the prospect of being married to this man of "powerful will" again, Louise dies from shock and despair.
When the doctors arrived they said she had died of heart disease—of the joy that kills.
The doctors said she had died of "the joy that kills." They thought her joy was the joy of seeing that her husband was actually alive. In fact, her reaction to his appearance was the opposite. This is an example of verbal irony because what the doctors said was actually true, but not in the way they thought. Louise died because she had been exposed to a pure, living joy that she would never have experienced if her husband had simply come home that day like usual. It was not her day-to-day unhappiness that killed her. Experiencing freedom and happiness for the span of one hour and then realizing that she was still trapped resulted in her death.