formation

noun

for·​ma·​tion fȯr-ˈmā-shən How to pronounce formation (audio)
1
: an act of giving form or shape to something or of taking form : development
2
: something that is formed
new word formations
3
: the manner in which a thing is formed : structure
the peculiar formation of the heart
4
: a major kind of plant growth (such as forest, grassland, or tundra) characteristic of a broad ecological region
5
a
: any igneous, sedimentary, or metamorphic rock represented as a unit
b
: any sedimentary bed or consecutive series of beds sufficiently homogeneous or distinctive to be a unit
6
: an arrangement of a body or group of persons or things in some prescribed manner or for a particular purpose
flying in formation

Examples of formation in a Sentence

The book explains the formation of the planets. The soldiers were marching in formation. The team ran on the field and lined up in a punt formation.
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.
Read More: TikTok Restores Service For U.S. Users Based on Trump's Promised Executive Order During the 1970s, people-to-people exchanges sought to bridge the gap between two nations that had lacked formal diplomatic relations since the formation of the People’s Republic of China (PRC) in 1949. Mark Tseng-Putterman / Made By History, TIME, 10 Mar. 2025 During a summertime visit, guests can marvel at huge crowds of northern gannets packed onto the surface of the formation, while other potential seabird sightings span from the common murre to the black-legged kittiwake to the little auk. Jared Ranahan, Forbes, 9 Mar. 2025 Asteroids are inactive bodies orbiting the sun, usually composed of rocky, dusty and metallic materials left behind from the formation of our solar system about 4.6 billion years ago. Tommy Tuberville, Newsweek, 7 Mar. 2025 Asteroid nearly hits Earth in Siberia, with a 2nd massive asteroid passing this week The meteorite strike may have even contributed to the formation of cratons, which are large, stable landmasses that became the foundation of continents, Kirkland said. Julia Jacobo, ABC News, 7 Mar. 2025 See All Example Sentences for formation

Word History

First Known Use

15th century, in the meaning defined at sense 1

Time Traveler
The first known use of formation was in the 15th century

Browse Nearby Words

Cite this Entry

“Formation.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/formation. Accessed 16 Mar. 2025.

Kids Definition

formation

noun
for·​ma·​tion fȯr-ˈmā-shən How to pronounce formation (audio)
1
: a forming of something
2
: something formed
3
: the manner in which a thing is formed : structure, shape
4
: a bed of rocks or series of beds recognizable as a unit
5
: an arrangement or grouping of persons, ships, or airplanes

Medical Definition

formation

noun
for·​ma·​tion fȯr-ˈmā-shən How to pronounce formation (audio)
1
: an act of giving form or shape to something or of taking form : development
2
: the manner in which a thing is formed : structure

More from Merriam-Webster on formation

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