fusion

noun

fu·​sion ˈfyü-zhᵊn How to pronounce fusion (audio)
Synonyms of fusion
often attributive
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 Republicans …—New York 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 Japanese-Peruvian 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

Synonyms of 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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Chinese defense materials describing the event say its goal is to advance China’s military-civil fusion strategy. — Melissa Lee,paige Tortorelli,scott Zamost, CNBC, 7 July 2026 Chasing fusion fuel Securing enough tritium remains one of the biggest challenges facing commercial fusion energy. — Neetika Walter, Interesting Engineering, 8 July 2026 There’s the restaurant, the trattoria, the café, the Tuscan-Oriental fusion spot, and a new outpost inside the Helvetia & Bristol Hotel. — Laura Itzkowitz, Travel + Leisure, 8 July 2026 As one of the first mainstream bands with a diverse mix of Black, white, male, and female musicians and a unique fusion of R&B and psychedelic rock, Sly and the Family Stone became an irrepressible force. — Al Shipley, SPIN, 7 July 2026 See All Example Sentences for fusion

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1

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

Phrases Containing fusion

Rhymes for fusion

See All Rhymes for fusion

Browse Nearby Words

fusinization
fusion
fusional
See all Nearby Words

Cite this Entry

“Fusion.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fusion. Accessed 10 Jul. 2026.

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Kids Definition

fusion

noun
fu·​sion ˈfyü-zhən How to pronounce fusion (audio)
1
: the act or process of melting or making fluid by heat
2
: union by or as if by melting
3
: the union of light atomic nuclei to form heavier nuclei resulting in the release of enormous quantities of energy

Medical Definition

fusion

noun
fu·​sion ˈfyü-zhən How to pronounce fusion (audio)
often attributive
1
a
: 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
c
(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

fusional
-ᵊl How to pronounce fusion (audio)
adjective

More from Merriam-Webster on fusion

Nglish: Translation of fusion for Spanish Speakers

Britannica.com: Encyclopedia article about fusion

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