* Latin: "signare" (to mark, to seal) - This is the root of the word.
* Medieval Latin: "signatura" (a mark, a seal) - This is the first recorded use of the word "signature" in its current sense.
* Middle English: "signatur" (a mark, a seal) - The word was borrowed into English during the Middle Ages, where it was initially used to refer to the marks and seals used to authenticate documents.
* Modern English: "signature" (a person's handwritten name, a distinguishing characteristic) - Over time, the meaning of the word evolved to encompass both literal marks and figurative ones, such as a person's unique style or characteristic.
Therefore, the origin of the word "signature" lies in the act of marking or sealing, which was used to authenticate documents and identify individuals in ancient times. This practice has evolved over centuries, giving the word "signature" its multifaceted meanings we use today.