|an arrangement of five objects, as trees, in a square or rectangle, one at each corner and one in the middle.|
|the offspring of a zebra and a donkey.|
|ventifact (věn'tə-fākt') Pronunciation Key
A rock or pebble that has been shaped, polished, or faceted by wind-driven sand.
stone that has received one or more highly polished, flattened facets as a result of erosion by windblown sand. The facets are cut in sequence and correlate with the dominant wind direction. As one surface is cut, the stone may become out of balance and may turn to expose another surface to the wind. A ventifact that has been eroded to three curved facets is called a dreikanter. Ventifacts are produced under arid conditions and are generally formed from hard, fine-grained rocks such as obsidian, chert, or quartzite.
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