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fu·sion (fyzhən)
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n.
1. The act or procedure of liquefying or melting by the application of heat.
2. The liquid or melted state induced by heat.
3.
a. The merging of different elements into a union: the fusion of copper and zinc to form brass; the difficult fusion of conflicting political factions.
b. A union resulting from fusing: A fusion of religion and politics emerged.
4. Physics A nuclear reaction in which atomic nuclei combine to form more massive nuclei with the simultaneous release of energy.
5. Music that blends jazz elements and the heavy repetitive rhythms of rock. Also called jazz-fusion, jazz-rock.
6. A style of cooking that combines ingredients and techniques from very different cultures or countries.

[Latin fūsiō, fūsiōn-, from fūsus, past participle of fundere, to melt; see gheu- in the Appendix of Indo-European roots.]
(click for a larger image)
fusion

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 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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