1. To remove something (from something else) by scraping with something hard, sharp, or abrasive. A noun or pronoun can be used between "scratch" and "away." I was left with a scar because I kept scratching the scab away. You can use a coin to scratch away the grey strip to reveal whether or not you won the prize.

2. To scrape something or some surface steadily or continuously with something hard, sharp, or abrasive. We've been scratching away for nearly an hour, but this rust just won't come off. The dog scratched away at the door, whining to be let out into the back yard.