[ fawr-mey-shuhn ]
See synonyms for: formationformational on

  1. the act or process of forming or the state of being formed: the formation of ice.

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

  1. Military.

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

    • any required assembling of the soldiers of a unit.

  2. Geology.

    • a body of rocks classed as a stratigraphic unit for geologic mapping.: Compare member (def. 8).

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

Origin of formation

1375–1425; late Middle English formacioun<Latin fōrmātiōn- (stem of fōrmātiō), equivalent to fōrmāt(us) (see form, -ate1) + -iōn--ion

Other words for formation

Other words from formation

  • for·ma·tion·al, adjective
  • mis·for·ma·tion, noun
  • non·for·ma·tion, noun
  • self-for·ma·tion, noun
  • sub·for·ma·tion, noun
  • su·per·for·ma·tion, noun

Words Nearby formation Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use formation in a sentence

British Dictionary definitions for formation


/ (fɔːˈmeɪʃən) /

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

  2. something that is formed

  1. the manner in which something is formed or arranged

    • 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

    • (as modifier): formation dancing

  2. geology

    • the fundamental lithostratigraphic unit

    • a series of rocks with certain characteristics in common

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

Derived forms of formation

  • formational, adjective

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for formation


[ fôr-māshən ]

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

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.