fiction

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The category of literature, drama, film, or other creative work whose content is imagined and is not necessarily based on fact.
• noun Works in this category.
• noun A work within this category.
• noun Narrative, explanatory material, or belief that is not true or has been imagined or fabricated.
• noun A narrative, explanation, or belief that may seem true but is false or fabricated.
• noun Law A verbal contrivance that is in some sense inaccurate but that accomplishes a purpose, as in the treatment of husband and wife as one person or a corporation as an entity.

from The Century Dictionary.

• noun The act of making or fashioning.
• noun The act of feigning, inventing, or imagining; a false deduction or conclusion: as, to be misled by a mere fiction of the brain.
• noun That which is feigned, invented, or imagined; a feigned story; an account which is a product of mere imagination; a false statement.
• noun In literature: A prose work (not dramatic) of the imagination in narrative form; a story; a novel.
• noun Collectively, literature consisting of imaginative narration; story-telling.
• noun In a wide sense, not now current, any literary product of the imagination, whether in prose or verse, or in a narrative or dramatic form, or such works collectively.
• noun In law, the intentional assuming as a fact of what is not such (the truth of the matter not being considered), for the purpose of administering justice without contravening settled rules or making apparent exceptions; a legal device for reforming or extending the application of the law without appearing to alter the law itself.
• noun Synonyms Fabrication, figment, fable, untruth, falsehood.

from the GNU version of the Collaborative International Dictionary of English.

• noun The act of feigning, inventing, or imagining.
• noun That which is feigned, invented, or imagined; especially, a feigned or invented story, whether oral or written. Hence: A story told in order to deceive; a fabrication; -- opposed to fact, or reality.
• noun Fictitious literature; comprehensively, all works of imagination; specifically, novels and romances.
• noun (Law) An assumption of a possible thing as a fact, irrespective of the question of its truth.
• noun Any like assumption made for convenience, as for passing more rapidly over what is not disputed, and arriving at points really at issue.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Literary type using invented or imaginative writing, instead of real facts, usually written as prose.
• noun uncountable Invention.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a deliberately false or improbable account
• noun a literary work based on the imagination and not necessarily on fact