1 [U] the action of forming sth; the process of being formed:
An agreement on the formation of a new government was reached on June 6. * evidence of recent star formation in the galaxy
2 [C] a thing that has been formed, especially in a particular place or in a particular way:
massive rock formations
3 [U,C] a particular arrangement or pattern:
aircraft flying in formation * formation flying / dancing * Flying low across the river was a formation of swans-five of them at least.
