Kahekihilise

Kahekihilise is an Estonian adjective meaning two-layered or bilayer. It is used to describe objects or structures that consist of two distinct layers. The term is common in technical and scientific texts in Estonian and is applied across fields such as geology, materials science, and engineering. The base form is kihiline (“layered”), and kahe- is a prefix meaning “two”; combined, kahekihiline denotes something that has two layers. The inflected form kahekihilise occurs when the adjective modifies a noun in the genitive case, for example in “kahekihilise kattekihi paksus” (the thickness of a two-layer coating) or “kahekihilise koostisega materjal” (a material with a bilayer composition).

In geology, kahekihiline describes rocks or sediments that show two distinct stratigraphic layers, each with different mineralogy or grain size. In materials science and engineering, it is used for laminates, coatings, membranes, or sandwich structures consisting of two functional layers. The concept is descriptive rather than a formal taxonomic term, and different disciplines may define what qualifies as a “layer” in its own way.

Related terms include ühekihiline (one-layered) and kolmekihiline (three-layered). The phrase is not a proper noun and does not refer to a specific place, organism, or organization, but rather to a grammatical descriptor in Estonian.