fusion

American  

[fyoo-zhuhn] / ˈfyu ʒən /

noun

1. the act or process of fusing; the state of being fused.

2. that which is fused; the result of fusing.

   A ballet production is the fusion of many talents.

3. Politics.

   1. a coalition of parties or factions.

   2. (initial capital letter) the political party resulting from such a coalition.

4. Also called nuclear fusion.  Physics. a thermonuclear reaction in which nuclei of light atoms join to form nuclei of heavier atoms, as the combination of deuterium atoms to form helium atoms.

5. Ophthalmology

   1. Also called binocular fusion.  the correct blending of the images of both eyes.

   2. the perception of rapid, intermittent flashes of light as a continuous beam.

6. popular music that is a blend of two styles, especially a combining of jazz with either rock, classical music, or such ethnic elements as Brazilian or Japanese music.

7. Linguistics. the merging of linguistic elements, especially morphemes, usually accompanied by a change in the form of the elements.

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adjective

1. (of food or cooking) combining usually widely differing ethnic or regional ingredients, styles, or techniques.

   a restaurant serving French-Thai fusion cuisine; a fusion menu.

fusion British  

/ ˈfjuːʒən /

noun

1. the act or process of fusing or melting together; union

2. the state of being fused

3. something produced by fusing

4. See nuclear fusion

5. the merging of juxtaposed speech sounds, morphemes, or words

6. a coalition of political parties or other groups, esp to support common candidates at an election

7. a kind of popular music that is a blend of two or more styles, such as jazz and funk

8. psychol the processing by the mind of elements falling on the two eyes so that they yield a single percept

9. (modifier) relating to a style of cooking which combines traditional Western techniques and ingredients with those used in Eastern cuisine

   fusion cuisine

   fusion food

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fusion Scientific  

/ fyo̅o̅′zhən /

1. The joining together of atomic nuclei, especially hydrogen or other light nuclei, to form a heavier nucleus, especially a helium nucleus. Fusion occurs when plasmas are heated to extremely high temperatures, forcing the nuclei to collide at great speed. The resulting unstable nucleus emits one or more neutrons at very high speeds, releasing more energy than was required to fuse the nuclei, thereby making chain-reactions possible, since the reaction is exothermic. Fusion reactions are the source of the energy in the Sun and in other stars, and in hydrogen bombs.

2. See also fission

3. A mixture or blend formed by fusing two or more things.

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Other Word Forms

• fusional adjective
• nonfusion noun

Etymology

Origin of fusion

First recorded in 1545–55; from Latin fūsiōn- (stem of fūsiō ) “a pouring out, melting”; fuse ², -ion; fusion def. 4 was first recorded in 1945–50

Example Sentences

Future iterations would add Boron-11 here to begin fusion.

From The Wall Street Journal • Mar. 28, 2026

Future iterations would add Boron-11 here to begin fusion.

From The Wall Street Journal • Mar. 28, 2026

For Nunes, the ambition is building a campus capable of generating thousands of megawatts of electricity—and beating China in the fusion race.

From The Wall Street Journal • Mar. 28, 2026

Experts generally agree fusion has great potential, but many consider commercial viability at least a decade away.

From The Wall Street Journal • Mar. 28, 2026

As the sensitivity of the neutrino telescope improves, it may become possible to probe nuclear fusion in the deep interiors of the nearby stars.

From "Cosmos" by Carl Sagan

Related Words

• amalgam
• blend
• blending
• synthesis