refraktives

Refraktives is a German adjective meaning refractive, used in technical writing to describe substances or phenomena that bend light, or, in some contexts, materials that withstand high temperatures. The form refraktives is the neuter singular nominative or accusative ending; the base adjective is refraktiv. In English-language optics, the corresponding term is refractive, and the related noun is refraction; the concept most closely associated is the refractive index, governed by Snell's law.

In optics, an item described as refraktives refers to a material or surface that refracts light, altering its direction and speed. The effect is governed by the refractive index of the material and Snell's law. Common examples are lenses made of glass or crystal.

In materials science, the term may appear in German as refraktives Material to denote heat-resistant materials, though the standard adjective is refraktär, and English speakers typically say refractory. Refractory materials include ceramics and metals that retain strength at high temperatures, such as alumina, zirconia, and tungsten.

Usage notes: The term is more common in German; in English technical writing 'refractive' or 'refractoriness' is used for these meanings. The word's dual meaning requires context to interpret correctly.

See also: Refraction, Refractive index, Snell's law, Refractory materials.