weathering

noun4

1. •
   Mechanical or chemical breaking down of rocks in situ by weather or other causes.

   • Furthermore, changes in continental weathering and riverine contributions to the oceans may also be linked with climate, and hydrothermal inputs vary with tectonism. — 1997
2. •
   The action of weather on objects exposed to it.
3. •
   A slight inclination given to an approximately horizontal surface to enable it to throw off water.
4. •
   (no longer used) Weather, especially favourable or fair weather.