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

Scroll down for the 16 best edge tamers at a variety of price points that will keep those bad boys on point and firmly in formation. Shammara Lawrence, Allure, "16 Edge Control Products That Keep Your Baby Hairs Super Sleek," 18 Sep. 2018 Iraqi political analyst Basim al-Awadi said the targeting of the Green Zone appeared intended to send a message to the U.S. against interfering in the formation of a government. Isabel Coles And, WSJ, "Rockets Fired Toward U.S. Diplomatic Missions in Iraq," 8 Sep. 2018 Bodyguards escorted Maduro out of the event and television footage showed uniformed soldiers standing in formation quickly scattering from the scene. Scott Smith And Christine Armario, Fox News, "Venezuela's Maduro: Drone attack was attempt to kill him," 5 Aug. 2018 There’s a volcano, a desert scene and an ice formation, among others. Ally Marotti,, "Pokemon Go Fest is back and ready for the crowds after disappointing thousands last year," 12 July 2018 Earlier this month, people near Memphis, Tennessee, spotted an odd formation in the sky after a storm. Caitlin O'kane, CBS News, "Ominous UFO-like cloud identified as rare "roll cloud"," 24 June 2018 The dyeing poison frog (Dendrobates tinctorius) lives on the forest floor in the lowland tropical rainforests of South America’s Guiana Shield, an ancient geological formation underlying the northeastern coast and parts of Venezuela and Brazil. Michael Allen, Science | AAAS, "How bright colors help these poison tree frogs hide from predators," 13 June 2018 Around 70 million years ago, Bonaire was an underwater mountain-like formation. Daily Intelligencer, "The Adventure-Seeker’s Guide to the Caribbean," 10 Apr. 2018 For example, visitors to Dinkins’ office were separated from the former mayor by an array of objects lined up at the perimeter of his desk like an army formation. Mary Carole Mccauley,, "Lewis museum photo exhibit 'Reflections' looks into lives of prominent black Americans," 17 Mar. 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


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Last Updated

14 Nov 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

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a private place of worship

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