Merriam-Webster Collegiate Dictionary - erode

 verb  (~d; eroding)  Etymology: Latin ~re to eat away, from e- + rodere to gnaw — more at rodent  Date: 1612  transitive verb  1. to diminish or destroy by degrees:  a. to eat into or away by slow destruction of substance (as by acid, infection, or cancer)  b. to wear away by the action of water, wind, or glacial ice flooding ~d the hillside  c. to cause to deteriorate or disappear as if by eating or wearing away inflation eroding buying power  2. to produce or form by eroding glaciers ~ U-shaped valleys  intransitive verb to undergo erosion where the land has ~d away  • erodibility noun  • erodible also erodable adjective