noun

• The act of abrading, wearing, or rubbing off; the wearing away by friction.
• (obsolete) The substance thus rubbed off; debris.
• (geology) The effect of mechanical erosion of rock, especially a river bed, by rock fragments scratching and scraping it.
• An abraded, scraped, or worn area.
• (medicine) A superficial wound caused by scraping; an area of skin where the cells on the surface have been scraped or worn away.
• (dentistry) The wearing away of the surface of the tooth by chewing.