Gerus

Gerus is a term used in Malay and Indonesian languages to denote wear, abrasion, or erosion of materials due to mechanical action. The noun refers to the process itself, while the related verb menggerus means to wear away or erode. The noun gerusan can denote the act of wearing away or the resulting abrasion.

In geology and geomorphology, gerus describes material removal caused by friction, transport of particles, or wind and wave action. In materials science and engineering, it is used to describe surface wear and thickness loss in components such as metals, stones, or ceramics through relative motion, impact, or corrosive processes. The concept overlaps with erosion, abrasion, and pengikisan, though usage may vary by discipline and language.

Causes of gerus include particle-particle or particle-surface contact, fluid flow carrying abrasive grains, weathering by water, wind, or ice, and mechanical actions such as grinding or rubbing. Conditions such as humidity, temperature, and the hardness of materials influence the rate and pattern of wear.

Effects of gerus can include surface thinning, pitting, rounding of edges, loss of fine features, and, over time, structural degradation in affected objects or landscapes. Recognizing gerus helps explain changes in material performance, coastal or riverine landscapes, and worn components in machinery.

See also: erosi, abrasi, pengikisan, aus.