n. The act of demonstrating; an exhibition; proof; especially, proof beyond the possibility of doubt; indubitable evidence, to the senses or reason.n. An expression, as of the feelings, by outward signs; a manifestation; a show. See also sense 7 for a more specific related meaning.n. The exhibition and explanation of a dissection or other anatomical preparation.n. (Mil.) a decisive exhibition of force, or a movement indicating an attack.n. The act of proving by the syllogistic process, or the proof itself.n. A course of reasoning showing that a certain result is a necessary consequence of assumed premises; -- these premises being definitions, axioms, and previously established propositions.n. a public gathering of people to express some sentiment or feelings by explicit means, such as picketing, parading, carrying signs or shouting, usually in favor of or opposed to some action of government or of a business.n. the act of showing how a certain device, machine or product operates, or how a procedure is performed; -- usually done for the purpose of inducing prospective customers to buy a product.