Final answer:
The theme is the underlying meaning or big idea in a work of literature that the author wants readers to understand.
Step-by-step explanation:
The underlying meaning or big idea that an author is trying to convey in a work of literature is called the theme. The theme is the central message or insight that the author wants readers to take away from the story. It is a universal and timeless idea that can be applied to the real world. For example, in the novel To Kill a Mockingbird by Harper Lee, one of the themes is the destructive nature of prejudice and racism.
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