rhombisch

Rhombisch is a German adjective meaning "rhombic" in English, used to describe shapes, patterns and structures related to or resembling a rhombus. A rhombus is a quadrilateral with four sides of equal length; opposite angles are equal but adjacent angles generally differ unless the shape is a square. The term rhombisch applies to objects composed of, patterned by, or based on rhombuses.

In geometry and tessellations, rhombic patterns appear in tilings where the plane is covered by congruent rhombi or by combinations of rhombi with other polygons. Famous examples include certain Penrose tilings and rhombic tilings used in decorative mosaics. In polyhedral geometry, names such as rhombic dodecahedron denote polyhedra whose faces are rhombi.

In crystallography and materials science, rhombisch is sometimes used historically or informally to refer to the orthorhombic crystal system (also called the rhombic system), characterized by three mutually perpendicular axes of unequal length. The adjective may also describe lattice sections, cleavage patterns or habit forms that exhibit rhombic symmetry or outline.

Etymologically, the word derives from the Greek rhombos, meaning a spinning top or something that turns, via Latin and Germanic forms; the German suffix -isch converts the noun into an adjective. Usage is largely descriptive and appears across mathematics, design, architecture and the physical sciences to denote rhombus-like form or symmetry.