FORMATION

noun Date: 15th century an act of giving form or shape to something or of taking form ; development , something that is formed , the manner in which a thing is formed ; structure , a major kind of plant growth (as forest, grassland, or tundra) characteristic of a broad ecological region, 5. any igneous, sedimentary, or metamorphic rock represented as a unit, any sedimentary bed or consecutive series of beds sufficiently homogeneous or distinctive to be a unit, an arrangement of a body or group of persons or things in some prescribed manner or for a particular purpose