التعريف: An isolated hill with steep sides and a small flat top, smaller than mesas and plateaus. Buttes are formed by erosion when a cap of hard rock, usually of volcanic origin, covers a layer of softer rock that is easily worn away. This hard rock avoids erosion while the rock around it wears down.
التعريف: The gnawing and biting-off of small fragments of tissue, whether from plants or dead invertebrates. [ https://www.worldcat.org/search?q=bn%3A0-412-40180-0 ]
