- Formation For*ma"tion (f[o^]r*m[=a]"sh[u^]n), n. [L. formatio:
cf. F. formation.]
1. The act of giving form or shape to anything; a forming; a
4. (Geol.) (a) Mineral deposits and rock masses designated with reference to their origin; as, the siliceous formation about geysers; alluvial formations; marine formations. (b) A group of beds of the same age or period; as, the Eocene formation. [1913 Webster]
5. (Mil.) The arrangement of a body of troops, as in a square, column, etc. --Farrow. [1913 Webster]
The Collaborative International Dictionary of English. 2000.