Noncubic

Noncubic is an adjective used to describe something that is not cubic. The term is used across disciplines to denote the absence of cubic form, symmetry, or degree. In everyday language it may simply refer to objects that are not cubes, while in technical contexts it distinguishes noncubic cases from those that are cubic in structure or behavior.

In mathematics, a noncubic polynomial is a polynomial whose degree is not three. This includes linear, quadratic, quartic, quintic, and higher-degree polynomials. Functions that are not cubic can still exhibit local features reminiscent of cubic curves, but they do not have the defining shape or curvature of a cubic polynomial.

In crystallography, the cubic crystal system is defined by equal lattice parameters a = b = c and all interaxial angles equal to 90 degrees, producing high symmetry. Noncubic crystals belong to other systems such as tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, and rhombohedral. The absence of cubic symmetry affects unit cell geometry, diffraction patterns, and macroscopic properties such as anisotropy.

In other contexts, noncubic describes shapes and structures that are not cubes, including spheres, pyramids, prisms, and irregular polyhedra. The term is primarily descriptive and is used when a contrast with cubic forms is helpful for classification or analysis.