for·ma·tion | \ fȯr-ˈmā-shən \

Definition of formation 

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

5a : 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

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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.
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Recent Examples on the Web

Kaegi faces Republican Joseph Paglia, who has yet to report formation of a campaign committee, in the November general election. Hal Dardick,, "Berrios' analysts used Zillow, other shortcuts in assessing property values, documents show," 13 July 2018 Since then, Lang Lang has achieved global popularity and, back home in China, has been credited with inspiring millions of kids to take up Western classical piano — aided by the formation of the Lang Lang International Music Foundation. David Patrick Stearns,, "Lang Lang's recovery: Will he ever play in Philly again?," 12 July 2018 This marks the earliest formation of a season's 2nd hurricane since 2005. Hurricane Chris, CBS News, "Hurricane Chris sending risky surf ashore as it swirls off East Coast," 11 July 2018 The final product, Bourzac explains, relied on the formation of silver-mercury-gold particles at points where light had struck the plate during the portrait sitting. Meilan Solly, Smithsonian, "Particle Accelerator Reveals Hidden Faces in Damaged 19th-Century Daguerreotype Portraits," 10 July 2018 Cooley also advised on the formation of Helix in 2015, launched with a $100 million investment. Bradley J. Fikes,, "Personal genomics company Helix raises $200 million," 9 July 2018 Acidic ingredients, including wine, beer, orange juice, pineapple and vinegar, help break down protein in the meat, which helps reduce the formation of HCAs. Andrea Thelen, Ms, Detroit Free Press, "6 tips for healthy and safe grilling," 9 July 2018 Team News Uruguay switched from the usual 4-4-2 formation to a more fluid 4-3-2-1 against Russia and reaped the benefits, but Oscar Tabarez will probably revert to type in expectation of a low-scoring game., "World Cup Preview: Uruguay vs Portugal - Statistics, Team News, Predictions & More," 29 June 2018 All those bare rock formations and unmarred tree trunks are just begging to be graced with your artistic vision. Madeleine Trebenski, Outside Online, "Rules of the Trail for Terrible People," 1 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'formation.' 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 formation

15th century, in the meaning defined at sense 1

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Dictionary Entries near formation






formation rule


Phrases Related to formation

break formation

Statistics for formation

Last Updated

5 Sep 2018

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Time Traveler for formation

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

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More Definitions for formation



English Language Learners Definition of formation

: the act of forming or creating something

: something that is formed or created

: an orderly arrangement or group of people, ships, or airplanes


for·ma·tion | \ fȯr-ˈmā-shən \

Kids Definition of formation

1 : a creation or development of something the formation of good habits

2 : something that is formed or created a cloud formation

3 : an arrangement of something battle formation punt formation


for·ma·tion | \ fȯr-ˈmā-shən \

Medical Definition of formation 

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

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Comments on formation

What made you want to look up formation? Please tell us where you read or heard it (including the quote, if possible).


the setting in which something occurs

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