for·​ma·​tion | \ fȯr-ˈmā-shən How to pronounce formation (audio) \

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

One of the latest developments is the formation of the local committee that will work with architects and planners to help chart the course of the project. Catalina Righter,, "Further East Middle discussion set for Sept. 18," 9 Sep. 2019 The play worked, but the formation was, umm, unusual? Mark Heim |, al, "Watch Florida State run play with WR facing wrong way vs. Louisiana Monroe," 7 Sep. 2019 But that formation might not be Portland’s best option against every opponent. Jamie Goldberg,, "Portland Timbers forward Brian Fernandez unlikely to move to the wing," 28 Aug. 2019 The formation of the Pakistan Air Force was to be a slow and laborious business. Raghvendra Singh, Quartz India, "What Britain gained by partitioning the subcontinent into India and Pakistan," 9 Aug. 2019 Spurred in part by Kadanoff’s work, physicists in the early 1990s demonstrated, first theoretically and then experimentally, that droplet formation is a universal phenomenon. Quanta Magazine, "Bubble Experiment Finds Universal Laws," 31 July 2019 Within the formation is a tract of land in Garfield County, Montana, that was previously owned by George Severson. Jeremy P. Jacobs, Science | AAAS, "Are dinosaur fossils ‘minerals’? The Montana Supreme Court will decide high stakes case," 10 July 2019 The formation of this particular storm is unusual, as an area of low pressure from the Tennessee Valley moved south this week into the Gulf of Mexico, said Benjamin Schott, a meteorologist at the National Weather Service. Brent Kendall, WSJ, "Gulf of Mexico States Brace for Potential Hurricane," 10 July 2019 However it is designated, Shahar said, the formation is a sign of a serious deformity in posture., "Horns are growing on young people’s skulls; researchers blame phone use," 22 June 2019

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


Statistics for formation

Last Updated

19 Sep 2019

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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 How to pronounce formation (audio) \

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 How to pronounce formation (audio) \

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).


concealment of treason or felony

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