means A person's name written in their own distinctive hand, used to authorize, identify, or claim something as their own.

from From the Latin signatura, 'a marking,' from signare, 'to mark or sign,' which traces back to signum, 'a sign or mark.' The same signum gave us 'sign,' 'signal,' and 'seal' — for centuries a mark of authority was a literal pressed image, the signet ring stamping wax. The word reached English through Medieval Latin and French, and by the time it settled into 'a written name' it carried all that older weight: the mark that stands in for the person.