the fact of soil, stone, etc. being gradually damaged and removed by the waves, rain, or wind

soil/coastal erosion 水土流失/海岸侵蚀

the fact of a good quality or situation being gradually lost or destroyed

The survey reveals a gradual erosion of the president's popularity and support. 民意调查显示了总统声望和所获支持的逐渐削弱。