The opposite of 'novel' could be 'familiar' or 'common'. For example, a novel idea is something new and different, while a familiar idea is something we already know well.
Well, the opposite of fiction is non - fiction. Fiction is made - up stories, like novels and short stories. Non - fiction, on the other hand, is all about real things. It can be informational books about nature, self - help books, or documentaries in written form. For example, a book about the history of the Roman Empire is non - fiction because it's based on historical research and real events.
The opposite of 'novel' could be 'familiar' or 'conventional'. Something novel is new and unique, so the opposite would be something that is common or not new.
Poetry could be considered the opposite in some ways. Novels tell stories through prose, but poetry uses a more condensed and lyrical form to express ideas and emotions.