Holograph

A holograph is a document written entirely in the handwriting of the person whose signature it bears. The laws of various U.S. states differ as to the validity of holographic last wills. See also autograph.

In the 20th century, the word "holographic" took on an additional meaning because of the invention of the photographic technique called holography. However, images produced using this technique are called "holograms", not holographs.