The word for today is…
signet (noun, verb):
noun
1: a seal used officially to give personal authority to a document in lieu of signature
2: the impression made by or as if by a signet
3: a small intaglio seal (as in a finger ring)
verb
: to stamp or authenticate with a signet
Source : Merriam -Webster
Etymology : Signets have been used for thousands of years. The design of a signet is personalized for its owner, and no two are alike. The ancients used signets to mark their possessions and to sign contracts. In later years signets were used to stamp a blob of hot wax sealing a folded secret document so that it couldn’t be opened and read without the design being broken. Nowadays you’re likely to hear of signets in reference to jewelry, especially rings. The reigning pope wears one, called the Fisherman’s Ring, which is carved with a figure of St. Peter encircled with the pope’s name; after a pope’s death, the ring is destroyed and a new one is made. If you guessed that signet and sign share an etymological relation, you’re entirely right: both can be traced to the Latin noun signum, meaning “a mark, token, image, sign, or seal.”
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