demonstration

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

• noun The act or process of providing evidence for or showing the truth of something.
• noun An illustration or explanation, as of a theory or product, by exemplification or practical application.
• noun A piece of evidence.
• noun An expression or manifestation, as of one's feelings.
• noun A public display of group opinion, as by a rally or march.

from The Century Dictionary.

• noun The act of pointing out or exhibiting; an exhibition; a manifestation; a show: as, a demonstration of friendship or sympathy.
• noun The exhibition and explanation of examples in teaching an art or a science, especially anatomy.
• noun Milit., an exhibition of warlike intentions; a warlike attitude or movement; specifically, a military operation of any kind which may be performed for the purpose of deceiving the enemy respecting the measures which it is intended to employ against him.
• noun A public exhibition, by a number of persons, of sympathy with some political or other cause, as in a mass-meeting or a procession.
• noun Proof, either a process of stating in an orderly manner indubitable propositions which evidently cannot be true without the truth of the conclusion so proved, or the propositions so Stated.
• noun In Roman law, the formal statement of the plaintiff's claim in presenting his case to the court: somewhat analogous to the ‘declaration’ of the common law.

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

• noun The act of demonstrating; an exhibition; proof; especially, proof beyond the possibility of doubt; indubitable evidence, to the senses or reason.
• noun An expression, as of the feelings, by outward signs; a manifestation; a show. See also sense 7 for a more specific related meaning.
• noun (Anat.) The exhibition and explanation of a dissection or other anatomical preparation.
• noun (Mil.) a decisive exhibition of force, or a movement indicating an attack.
• noun (Logic) The act of proving by the syllogistic process, or the proof itself.
• noun (Math.) 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.
• noun 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.
• noun 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.
• noun (Logic & Math.) one in which the correct conclusion is the immediate sequence of reasoning from axiomatic or established premises.
• noun (called also reductio ad absurdum), in which the correct conclusion is an inference from the demonstration that any other hypothesis must be incorrect.

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

• noun The act of demonstrating; showing or explaining something.
• noun An event at which something will be demonstrated.
• noun A public display of group opinion.
• noun A show of military force.
• noun A mathematical proof.

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

• noun proof by a process of argument or a series of proposition proving an asserted conclusion
• noun a public display of group feelings (usually of a political nature)
• noun a show of military force or preparedness
• noun a visual presentation showing how something works
• noun a show or display; the act of presenting something to sight or view