Weathering (7)
I believe the answer is:
erosion
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">weathering</span>' is the definition.<br/ ><span class="explanation-format__explanation">(thesaurus)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for erosion that I've seen before include "dying away" , "Action of wearing away" , "Process of wear" , "The wearing away as by wind or water" , "The wearing away by weather 97)" .)