Wiktionary
n. A large wind-eroded mass of soft or poorly consolidated rock in a desert region which lies parallel to the prevailing winds, often with an unusual shape.
Wikipedia
A yardang is a streamlined protuberance carved from bedrock or any consolidated or semiconsolidated material by the dual action of wind abrasion by dust and sand, and deflation which is the removal of loose material by wind turbulence. Yardangs become elongated features typically three or more times longer than wide, and when viewed from above, resemble the hull of a boat. Facing the wind is a steep, blunt face that gradually gets lower and narrower toward the lee end. Yardangs are formed by wind erosion, typically of an originally flat surface formed from areas of harder and softer material. The soft material is eroded and removed by the wind, and the harder material remains. The resulting pattern of yardangs is therefore a combination of the original rock distribution, and the fluid mechanics of the air flow and resulting pattern of erosion.
Usage examples of "yardang".
Iron Councillors build barricades in a yardang between set faces of cloud.
Sand dunes form and dissipate, and wind-sculpted patterns called yardangs are common.
The site was sheltered from ferocious winds, which had built the yardangs to westward.