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dem·on·stra·tion (dĕm′ən-strāshən)
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n.
1.
a. The act or process of providing evidence for or showing the truth of something: a demonstration of the drug's efficacy; a demonstration of the theorem.
b. An illustration or explanation, as of a theory or product, by exemplification or practical application: a demonstration of ballroom dancing.
2.
a. A piece of evidence: That car he bought is supposed to be a demonstration of his commitment to clean energy.
b. An expression or manifestation, as of one's feelings: a demonstration of her displeasure.
3. A public display of group opinion, as by a rally or march: peace demonstrations.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2020 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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