wear_away
1. [ verb ] diminish, as by friction
Synonyms: wear_off
Examples:

"Erosion wore away the surface"

Related terms: remove abrade
2. [ verb ] cut away in small pieces
Synonyms: whittle_down whittle_away
Related terms: damage
3. [ verb ] become ground down or deteriorate
Synonyms: erode gnaw_at gnaw eat_at
Examples:

"Her confidence eroded"

Related terms: decay erosion