Wiktionary
n. (context petrology English) A type of pebble that has three curved faces formed by wind-blown sand
Wikipedia
A Dreikanter is a type of ventifact that typically forms in desert or periglacial environments due to the abrasive action of blowing sand.
Dreikanters exhibit a characteristic three-faced pyramidal shape. The word Dreikanter is a German word meaning "three-edged."
A dreikanter is not to be confused with a zweikanter, which has only two sides, or an einkanter, which has only one windblown side.
Most places on the planet have several weathering processes acting at the same time, so finding good examples of Dreikanters is often difficult. Antarctica is a good location for finding such ventifacts since wind is usually the only active weathering agent. Many specimens in the Northeastern United States were formed during the Pleistocene era when the absence of vegetation made for little cover from wind-blown sediment.
Usage examples of "dreikanter".
So that there were einkanters with single facets, and dreikanters with three facets fierkanters, funfkanters-all the way up to nearly perfect hexahedrons, octahedrons, dodecahedrons.
So that there were einkanters with single facets, and dreikanters with three facets— fierkanters, funfkanters—all the way up to nearly perfect hexahedrons, octahedrons, dodecahedrons.