Carte blanche

CARTE BLANCHE. The signature of an individual or more, on a while. paper, with a sufficient space left above it to write a note or other writing.
     2. In the course of business, it not unfrequently occurs that for the sake of convenience, signatures in blank are given with authority to fill them up.. These are binding upon the parties. But the blank must be filled up by the very person authorized. 6 Mart. L. R. 707. Vide Ch. on Bills, 702 Penna. R. 200. Vide Blank.