Gradually wear away, as soil (5)
I believe the answer is:
erode
(Other definitions for erode that I've seen before include "'Deteriorate, wear away (5)'" , "Wear away with weather" , "Become ground down or deteriorate" , "fragment" , "Abrade" .)
I believe the answer is:
erode
(Other definitions for erode that I've seen before include "'Deteriorate, wear away (5)'" , "Wear away with weather" , "Become ground down or deteriorate" , "fragment" , "Abrade" .)