clivage

Clivage is a term used in several disciplines to denote a division or separation along specific lines, producing distinct groups, structures, or properties. The word comes from French, and its meaning varies by field, though it generally refers to a partition or the tendency of something to break or differentiate.

In political science and sociology, clivage refers to a persistent social division that shapes political behavior, party systems, and policy preferences. Classic cleavages identify deep-rooted antagonisms such as religion vs. state, rural vs. urban communities, center-periphery tensions, and owner vs. worker status. The concept helps explain why parties align with broad social blocs and why certain issues remain salient across elections. The idea is associated with scholars such as Lipset, Rokkan, and Sartori, who emphasized the durable impact of cleavages on political life.

In geology and mineralogy, clivage (or cleavage in English) describes a mineral’s tendency to break along flat, planar surfaces that reflect the crystal structure and bonds within the mineral. Cleavage is classified by the number of cleavage directions, the angles between them, and the quality of the break (perfect, good, distinct, or indistinct). It is a diagnostic property used to identify minerals and to understand their physical behavior.

In biology and embryology, clivage also refers to cleavage, the series of rapid mitotic divisions that convert a zygote into a multicellular embryo. This process precedes cell differentiation and organ formation and differs in rate and pattern among species.

Overall, clivage denotes a fundamental division or plane of separation, whether in social life, the natural properties of materials, or early developmental biology.