There is none. == == == == == == If by "novel" you mean "new," the antonym would be "old."
A possible antonym for fiction is nonfiction. Nonfiction refers to writing or stories that are based on real events and facts rather than being imaginary or made-up like fiction.
Non-fiction
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
The antonym of non-fiction is fiction. Fiction refers to imaginative or invented stories that are not based on real events or facts.
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'.