formation

American  

[fawr-mey-shuhn] / fɔrˈmeɪ ʃən /

noun

1. the act or process of forming or the state of being formed.

   the formation of ice.

   Synonyms:

   organization, establishment

2. the manner in which a thing is formed; disposition of parts; formal structure or arrangement.

3. Military.

   1. a particular disposition of troops, as in columns, squares, etc.

   2. any required assembling of the soldiers of a unit.

4. Geology.

   1. a body of rocks classed as a stratigraphic unit for geologic mapping.

   2. the process of depositing rock or mineral of a particular composition or origin.

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formation British  

/ fɔːˈmeɪʃən /

noun

1. the act of giving or taking form, shape, or existence

2. something that is formed

3. the manner in which something is formed or arranged

4. 1. a formal arrangement of a number of persons or things acting as a unit, such as a troop of soldiers, aircraft in flight, or a football team

   2. ( as modifier )

      formation dancing

5. geology

   1. the fundamental lithostratigraphic unit

   2. a series of rocks with certain characteristics in common

6. ecology a community of plants, such as a tropical rainforest, extending over a very large area

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formation Scientific  

/ fôr-mā′shən /

1. A long, mappable body of rock that is recognizable by its physical characteristics and by its location within the rock record.

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Other Word Forms

• formational adjective
• misformation noun
• nonformation noun
• self-formation noun
• subformation noun
• superformation noun

Etymology

Origin of formation

First recorded in 1375–1425; late Middle English formacioun, from Latin fōrmātiōn-, stem of fōrmātiō, from fōrmāt(us) “shaped” (past participle of fōrmāre “to shape, fashion”; form ) + -iō -ion

Example Sentences

He said: "Micrometeorites are samples of the Solar System's building blocks which can offer insights into early planetary formation, Earth's atmospheric history, and climate evolution."

From BBC • Apr. 4, 2026

"The moon is a witness plate to our entire solar system's formation," said astronaut Koch in a press conference over the weekend.

From Barron's • Apr. 1, 2026

Carrick followed Fletcher's lead in ditching Amorim's three at the back formation, pushed skipper Bruno Fernandes into a more forward role, recalled Kobbie Mainoo to play alongside Casemiro and stuck with it.

From BBC • Apr. 1, 2026

A new study led by Yongda Zhu at the University of Arizona suggests these black holes can also slow the formation of stars in galaxies located millions of light-years away.

From Science Daily • Mar. 30, 2026

The journey to the odd-looking rock formation that Fly spotted during his flight takes much longer than expected.

From "A Rover's Story" by Jasmine Warga

Related Words

• arrangement
• construction
• creation
• design
• development
• evolution
• forming
• pattern
• production
• structure