noun, often attributive
fu·​sion | \ ˈfyü-zhᵊn How to pronounce fusion (audio) \

Definition of fusion

1 : the act or process of liquefying or rendering plastic by heat
2 : a union by or as if by melting: such as
a : a merging of diverse, distinct, or separate elements into a unified whole Opera is a fusion of several arts.
b : a political partnership : coalition a fusion of Democrats and independent RepublicansN. Y. Times
c : popular music combining different styles (such as jazz and rock)
d : food prepared using techniques and ingredients of two or more ethnic or regional cuisines a restaurant that specializes in Indian-Chinese fusion

called also fusion cuisine

3 : the union of atomic nuclei to form heavier nuclei resulting in the release of enormous quantities of energy when certain light elements unite nuclear fusion

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Examples of fusion in a Sentence

a fusion of different methods a fusion of musical styles The show is a fusion of news and entertainment. The fusion of different cultural influences is evident in her sculpture.
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Recent Examples on the Web

Chandrayaan-2, which will explore the Moon's southern hemisphere, will also be looking for the isotope helium-3, which could be mined for use in nuclear fusion. David Grossman, Popular Mechanics, "India Is Going to the Moon in July," 13 June 2019 Miller has dined at establishments from San Francisco to Chicago serving African-American cuisine that’s traditional and health-conscious or vegetarian and vegan or upscale and fusion. Josie Sexton, The Denver Post, "Where has Denver’s soul food gone? In a historically black neighborhood, the last restaurant of its kind turns 20," 12 June 2019 From art fusion camps to filmmaking workshops and musical theater camps, Osceola Arts has options for young ones with many different interests. Patrick Connolly, orlandosentinel.com, "School’s out: How to have fun and get the kids away from screens this summer," 10 June 2019 If egg and sperm fusion had occurred, the offspring would have two alleles. Ryan W. Miller, USA TODAY, "Without the help of any male, this female lizard became pregnant alone and gave birth," 7 June 2019 Belly & Sweet Belly: Uptown Oakland will be represented in the new digs across the bay by Belly and Sweet Belly, a fusion eatery and dessert window from owner-operators Alan Chun and Alice Woo. Linda Zavoral, The Mercury News, "Warriors fans: Here are the first new Chase Center area restaurants," 3 June 2019 Fusion could deliver more energy more safely and with far less harmful radioactive waste than fission, but just a small number of people—including a 14-year-old from Arkansas—have managed to build working nuclear fusion reactors. National Geographic, "What is nuclear energy and is it a viable resource?," 26 Mar. 2019 Spinal fusion surgery is offered to patients with a severe curve of 50 degrees and above, but my curves, both of which measured at 28 degrees, are considered moderate. Lauren Depino, Glamour, "My Scoliosis Caused Me Pain and Shame—Then It Helped Me Learn to Find Alignment," 10 Apr. 2019 Some Chinese scientists see the moon’s abundant supplies of helium-3, a nonradioactive isotope, as a potential source of nuclear-fusion energy. Trefor Moss, WSJ, "China Pushes for Primacy in Space," 31 Dec. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fusion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fusion

14th century, in the meaning defined at sense 1

History and Etymology for fusion

borrowed from Medieval Latin fūsiōn-, fūsiō "process of pouring, casting of molten metal," going back to Latin, "process of pouring, effusion," from fud-, variant stem of fundere "to pour, shed, cast (liquid metal)" (Medieval Latin also, "to melt down, make liquid") + -tiōn-, -tiō, suffix of verbal action — more at found entry 5

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Statistics for fusion

Last Updated

18 Jun 2019

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Time Traveler for fusion

The first known use of fusion was in the 14th century

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More Definitions for fusion



English Language Learners Definition of fusion

: a combination or mixture of things
physics : a process in which the nuclei of atoms are joined
: a type of popular music that combines different styles (such as jazz and rock)


fu·​sion | \ ˈfyü-zhən How to pronounce fusion (audio) \

Kids Definition of fusion

1 : an act of fusing or melting together
2 : union by or as if by melting
3 : union of atomic nuclei to form heavier nuclei resulting in the release of enormous quantities of energy


noun, often attributive
fu·​sion | \ ˈfyü-zhən How to pronounce fusion (audio) \

Medical Definition of fusion

1a : the act or process of liquefying or rendering plastic by heat
b : the liquid or plastic state induced by heat
2 : a union by or as if by melting together: as
a : a merging of diverse elements into a unified whole specifically : the blending of retinal images in binocular vision
b : a combination of ingredients achieved by heating and mixing together


(1) : a blend of sensations, perceptions, ideas, or attitudes such that the component elements can seldom be identified by introspective analysis
(2) : the perception of light from a source that is intermittent above a critical frequency as if the source were continuous

called also flicker fusion

— compare flicker
d : the surgical immobilization of a joint — see spinal fusion
3 : the union of atomic nuclei to form heavier nuclei resulting in the release of enormous quantities of energy when certain light elements unite

called also nuclear fusion

Other Words from fusion

fusional \ -​ᵊl How to pronounce fusional (audio) \ adjective

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