However, depending on the context, you might use more specific terms like:
* Erosion: Used for the gradual wearing away of something by natural forces like wind, water, or ice.
* Abrasion: Used for the wearing away of something due to friction, like rubbing against a rough surface.
* Corrosion: Used for the wearing away of something due to chemical reactions, like rusting.
* Deterioration: Used for the general process of becoming worse or weaker, often due to wear and tear.
To provide a more accurate answer, please tell me what you are referring to. For example:
* "What is the wear on my shoes called?"
* "What is the wear on a metal surface called?"
* "What is the wear on a mountain called?"