formation

noun

for·​ma·​tion fȯr-ˈmā-shən 

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

Synonyms

• arrangement
• configuration
• conformation
• format
• layout
• setout
• setup

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

According to Esquire, the finale solidified Cassian's transformation from a cynical loner into a dedicated insurgent, setting up his role in the formation of the Rebel Alliance. —Thomas G. Moukawsher, MSNBC Newsweek, 25 Apr. 2025

Those wildfires produce the sooty particles that contribute to particulate pollution, while extreme heat creates more favorable conditions for ozone formation, producing smog. —Lillian Ali, Smithsonian Magazine, 25 Apr. 2025

Loveland, at 6-foot-6 and 248 pounds, is an elite pass-catching tight end and the type of chess piece who can move all across the formation and still be dangerous. —Sean Hammond, Chicago Tribune, 25 Apr. 2025

The Georgia safety had broken down plays and formations. —Jeff Zrebiec, New York Times, 25 Apr. 2025

Word History

First Known Use

15th century, in the meaning defined at sense 1

Phrases Containing formation

• back-formation
• break formation
• I formation
• punt formation
• reticular formation
• self-formation
• spread formation
• T formation

Rhymes for formation

• ablation
• bination
• carnation
• cassation
• castration
• causation
• centration
• cessation
• cetacean
• chelation
• citation
• collation

Kids Definition

formation

noun

for·​ma·​tion fȯr-ˈmā-shən 

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 

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