demonstration

noun

1. the act or circumstance of proving or being proved conclusively, as by reasoning or a show of evidence: a belief incapable of demonstration.
2. something serving as proof or supporting evidence: They sent a check as a demonstration of their concern.
3. a description or explanation, as of a process, illustrated by examples, specimens, or the like: a demonstration of methods of refining ore.
4. the act of exhibiting the operation or use of a device, machine, process, product, or the like, as to a prospective buyer.
5. an exhibition, as of feeling; display; manifestation: His demonstration of affection was embarrassing.
6. a public exhibition of the attitude of a group of persons toward a controversial issue, or other matter, made by picketing, parading, etc.
7. a show of military force or of offensive operations made to deceive an enemy.
8. Mathematics. a logical presentation of the way in which given assumptions imply a certain result; proof.

noun

1. the act of demonstrating
2. proof or evidence leading to proof
3. an explanation, display, illustration, or experiment showing how something works
4. a manifestation of grievances, support, or protest by public rallies, parades, etc
5. a manifestation of emotion
6. a show of military force or preparedness
7. maths a logical presentation of the assumptions and equations used in solving a problem or proving a theorem

n.

late 14c., “proof that something is true,” from Old French demonstration or directly from Latin demonstrationem (nominative demonstratio), noun of action from past participle stem of demonstrare “to point out, indicate, demonstrate,” figuratively, “to prove, establish,” from de- “entirely” (see de-) + monstrare “to point out, show,” from monstrum “divine omen, wonder” (see monster). Meaning “public show of feeling,” usually with a mass meeting and a procession, is from 1839. Related: Demonstrational.