changes to the colour or form of something over a period of time because of the effects of sun, wind, or other weather conditions

The fence had gone from brown to a soft grey through years of weathering. 经过常年的日晒雨淋，篱笆从棕色变成了浅灰色。

the processes by which rock is broken into smaller pieces by the action of the weather

Weathering has seriously eroded the caves. 风化作用严重地侵蚀了岩洞。