Sign manual is a term that refers to a written signature. However, there are various other terms that can be used to describe this action. One of the most common is autograph, which is a signature made by an individual on their own behalf. Another term is endorsement, which is a signature or mark that indicates approval of a document. Some other synonyms for sign manual include signature, scribble, sign, initials, and John Hancock. Difficult to decipher signatures may be referred to as a scrawl or a squiggle. In general, all of these terms refer to the act of signing a document or piece of paper to confirm its authenticity.