Demiaxes

Demiaxes is a term that appears in various mathematical discussions to denote a notion related to axes, but it does not have a single, universally accepted definition. In practice, the term is used inconsistently, and its precise meaning must be specified by the author in any given context.

One broad interpretation is that a demiaxis is a line that acts as an axis of symmetry only for part of a figure or object, rather than for the entire shape. Under this usage, the line identifies a mirror relationship within a restricted region, such as along a subcurve or a partial subshape, without extending to global symmetry of the whole figure. A related idea interprets a demiaxis as a half-line or ray that functions as a local axis within a limited domain.

A third common usage appears in data analysis and visualization, where demiaxes describe directions along which a dataset or image shows partial or region-specific symmetry, anisotropy, or regularity. In this setting, demiaxes are identified by local methods and may change with position or scale rather than being fixed global directions.

Because demiaxes lack a standardized definition, researchers are advised to define the term explicitly when it arises in literature. Related concepts include axis, symmetry axis, demi-axis in other contexts, and directions of partial invariance or anisotropy.