eroding

(noun) (geology) the mechanical process of wearing or grinding something down (as by particles washing over it). Synonyms: erosion, eating away, wearing, wearing away.

(verb) become ground down or deteriorate. Synonyms: erode, gnaw, gnaw at, eat at, wear away. Example: "Her confidence eroded."

(verb) remove soil or rock. Synonyms: erode, eat away, fret. Example: "Rain eroded the terraces."