There is none. == == == == == == If by "novel" you mean "new," the antonym would be "old."
Non-fiction
The opposite of non-fiction is fiction.
fiction
Fiction is.
The antonym (opposite) of the word fantasy would be reality, or truth.
science fiction, fantesy, romance, etc.
Fact. Real life. Non-fiction.
If you mean the word legend to mean epic or long story, then the antonym is short story. If legend means fable or fiction, the antonym is truth or nonfiction.
truth, reality, certainty, verity
Ah, the antonym for non-fiction is fiction, my friend. Non-fiction tells us about real people, places, and events, while fiction takes us on imaginative journeys to different worlds and possibilities. Both types of writing have their own beauty and purpose in the vast landscape of storytelling.
Synonyms for biography are life story, life history, and memoir.It is hard to find an antonyms for biography but a biography should not be a work of fiction or fantasy.
The antonym of the word 'synonym' is 'antonym'.