2. A small piece of marble, glass, etc. which was used in mosaic work or decorations made of small pieces of stone, glass, wood, etc of different colors inlaid to form a picture or a design.
3. In ancient history, a small quadrilateral tablet of wood, bone, ivory, or the like, used for various purposes, as a token, tally, ticket, label, etc.
4. A token or password; from a quest and host sharing a broken die.
5. A small piece of marble, glass, or the like, having a square, or nearly square, face, used in mosaic work, as for making pavements, the ornamenting of walls, etc.
6. In zoology, a small rectangular plate of bone, as found in the carapace of the armadillo. A carapace is a thick hard case or shell made of bone or chitin that covers part of the body; especially, the back of an animal such as a crab, turtle, or armadillo.
7. A curvilinear (curved or rounded) rectangle.
8. In Roman antiquity, a small cube of ivory, bone, wood, etc.
Used as a die in gambling or in the composition of mosaic.9. Etymology: from Greek tessares, "four" and from Latin "cube".
A similar piece, though often modified in shape, used as a ticket, token, certificate, etc.; such as:
- tessera fragmentaria (TES uh ruh fryoo” men TAY ri uh), a voucher for a dole of provisions.
- tessera hospitalis (TES uh ruh hahs” pi TAY lis), a pledge of hospitality and friendship, a token half of which was kept by each of two friends.
- tessera militaris (TES uh ruh mil” i TAY ris), a small billet or tablet, or the like, and distributed through the division of an army.
- tessera nummaria (TES uh ruh nuh MAY ri uh), a voucher for a dole of money.
- tessera theatratis (TES uh ruh thee” uh TRAY lis), a ticket for admission to the theater.
Why tessera also means “password” in Latin.
A watchword was used at night and it consisted of a word or phrase that someone must say to prove that he was a bona fide member of a Roman unit or, if the authorized password was not used, he was considered an enemy.
In the Roman army, the watchword for the night was not communicated verbally, but by means of a small rectangular tablet of wood upon which it was written. One man was chosen out of each of those maniples (common soldiers) and turmae (troop of cavalry containing thirty men, a squadron) that were quartered at that extremity of the lines most remote from the Principia.
Each of these individuals (tesserarius) went near sunset to the tent of the tribune, and received from him a tessera, on which the password and also a certain number or mark were inscribed.
With this he returned to the maniple or turma to which he belonged, and taking witnesses, delivered it to the officer of the next adjoining maniple or turma, and to the next until it had passed along the whole line. Then it was returned by the person who received it last to the tribune.
The regulation was that the whole of the tesserae should be restored before it was dark, and if any one was found not returning the tessera at the appointed time, the row to which it belonged could be quickly discovered by means of the number or mark at the top, and so an investigation took place as to the cause of the delay, and punishment was inflicted upon the parties found to be at fault.
Not only mere passwords were circulated in this manner, but also, occasionally, general orders. Although the tesserarius received the tessera from the tribune, it proceeded in the first instance from the commander-in-chief and others.
Under the Roman Empire it was considered the peculiar function of the prince to give the watchword to his guards.
From the application of this term to tokens of various kinds, it was transferred to the word used as a token among soldiers. This was the tessera militaris.
Before joining battle, it was given out and passed through the ranks as a method by which the soldiers might be able to distinguish friends from foes.
Thus at the battle of Cunaxa, the word was "Zeus the Saviour and Victor", and on a subsequent engagement by the same troops, it could be "Zeus the Saviour, Heracles the Leader".
The soldiers of Xenophon used a verbal sign for the same purpose when they were encamped at night.