You searched for: “cheirograph
cheirograph, chirograph (s) (noun); cheirographs, chirographs (pl)
1. A writing which, requiring a counterpart, was written twice on the same piece of parchment, with a space between, in which was written the word chirographum, through which the parchment was cut, and one part given to each party. It answered to what is now called a charter party.
2. Applied technically to the various documents that were formally written, engrossed, or signed "by hand" rather than by other means of publication.

A charter party, as mentioned in #1, is defined as an instrument in writing, from the sovereign power of a state or country, executed in due form, bestowing rights, franchises, or privileges.