an object (especially a ring) formerly used to impress a picture into the sealing wax of a document as a proof of its origin (noun)
Examples of word signet
It is like gold, or more exactly it is like the gold-coloured semi-precious stone which one sometimes sees in signet rings, and which I think is called a chrysoberyl.
But the order of male succession was asserted by the friends of their country; the lawful heir drew the royal signet from the finger of his insensible or conscious father and the empire obeyed the master of the palace.
Stampt with my signet are the swarthy children of the sun:
His signet is the Fisherman's; No sceptre does he bear;
Moses, who poured water upon the ground and it became blood; the signet is called the signet of truth, and is Zerrubbabel.