formation

Formation is the act or result of forming; the process by which something comes into being, is arranged, or takes shape. The term derives from the Latin formare, to form. In general use, formation refers to structure, pattern, or the way parts are combined.

In geology, a formation is a mappable body of rock with distinctive characteristics that distinguish it from neighboring rocks. Formations are named for geographic locality and are used in stratigraphy to organize the sequence of rocks. A formation may contain multiple lithologies and can be subdivided into units called members or beds.

In biology and developmental sciences, formation describes the development of tissues, organs, or organisms. Morphogenesis is the set of processes that shape form during embryonic development, while tissue formation and organ formation refer to the differentiation and assembly of cells into functional structures.

In astronomy, star formation occurs in molecular clouds when gravity causes gas and dust to coalesce, forming protostars and eventually mature stars. The term can also apply to planet formation in protoplanetary disks.

In chemistry and materials science, formation denotes the creation of a chemical compound or solid phase, often described by formation energy or formation enthalpy, which quantify the energy change during synthesis.

In social, military, and organizational contexts, formation refers to the arrangement of people or units for a purpose, such as a company’s legal formation, or a military formation like a line, column, or square.