Blank
Blank refers to an empty space or a surface without anything marked or written, such as a blank sky or blank paper. A blank tape has nothing recorded in it, a blank cheque has no amount written, a blank document is unsigned, a blank look is lack of emotion or comprehension, a blank to be filled is a space left to be filled, a blank cartridge has gunpowder but no bullet, a blank period is the period about which no knowledge is available, and so on.