If something is a blot on a person's or thing's reputation, it spoils their reputation. a blot on the reputation of the architectural profession This drugs scandal is another blot on the Olympics
If you describe something such as a building as a blot on the landscape, you mean that you think it is very ugly and spoils an otherwise attractive place. The developers insist the £80m village will not leave a blot on the landscape
A single checker on a point is called a blot If you move a checker onto an opponent's blot, or touch down on it in the process of moving the combined total of your cast, the blot is hit, removed from the board and placed on the bar
If you blot a surface, you remove liquid from it by pressing a piece of soft paper or cloth onto it. Before applying make-up, blot the face with a tissue to remove any excess oils