1. An opportunity to start fresh despite past mistakes or problems. I know we've had our differences, but I'd like to repair our friendship. Can we start with a clean sheet?
2. In sports, a game or series of games in which one side wins with the opposing side(s) being unable to score any points. Primarily heard in UK. The football team has kept a clean sheet for the last three games. I don't think anyone can score against them!