释义 |
roll stone U.S. A stone rounded by friction or attrition on a beach or in the bed of a river.
1845J. C. Frémont Rep. Exploring Expedition 124 A swift current, over a bed composed entirely of boulders or roll stones. 1872Rep. Vermont Board Agric. I. 688 A fine specimen of gold from a rollstone he found, while digging a well. |