This word was used in Greek solid geometry for the 6-sided cube and for the gambling die of that shape. The latter may have been the original meaning. This die may have reached Egypt and Greece as late as the seventh and sixth centuries B.C. respectively. Dice are regularly recovered in excavations such as at Corinth, and often show anomalies such as a nine in place of the six (see Davidson as reference below). Except in the use of the cubic die in board games (see tau 7, pi 1384) it was never as popular as the older dicing game (see OCD(4) s.v. 'dicing' and Daremberg-Saglio s.v. 'tessera') with four knucklebones (astragaloi), with its colorful jargon for each of the knucklebone's faces and for throws such as "Venus", "dogs" and "Euripides". The 6-sided die was thrown usually in threes in games that seem to have closely resembled modern zanzi and "421". The pot was increased by each gambler for each ace (one-spot) he threw (or for each ace or 6, in a game reported by Suetonius, Augustus 71, from a letter to Tiberius). The entire pot was won by the first player to throw triple 6, and this gave rise to the proverb "either triple 6 or three aces" (tau 1006, etc.). This game would have been highly addictive and may be the one known as pleistoboli/nda. Suetonius (p. 65) mentions a game played by "trematiktai", determining in advance the money value of each spot on the die (the meaning of kubos here is probably that given at Pollux 9.95, each 'spot', for that is the meaning of trh=ma). Euripides, in a line (Telephus?, fr. 888) selected ironically by Dionysus in Aristophanes' Frogs (1400), mentions the throw of two aces and a four, a throw that happens, perhaps coincidentally, to be the fourth-best throw of the modern game "421" (after 421, 611, 511). A line from Eupolis (fr. 342 Kock, now 372 K.-A.) with the same throw probably, but not necessarily, indicates, however, that it was a bad throw.
The headword was used in dicing in various meanings other than the actual die thrown (see LSJ, and Lamer 1935-7) and occasionally confused with the astragalos (Lamer 1937-8). In particular it was used (1) of the ace or one-spot on the die (see omicroniota 106), as in the above proverb and in the lines from Euripides and Eupolis, (2) of throws of the dice (or single die), perhaps of one particular throw (cf. Pollux 9.95, that it meant each pip marked or inscribed on the sides of the die). There is some evidence that the one-spot of the die was empty or unmarked (see discussion at tau 1006). A die might be "empty" or "full"; this we might interpret as hollow or solid, unmarked or marked or as referring to the same choice as given to the first player in modern dice games of choosing whether the game will be played as highest score wins or as lowest wins. The list of dice throws given by Eubulus fr. 57 Kock and K.-A., and in Lamer (1945-58), includes chiefly throws from astragaloi-games or board-games (see pi 1384), rather than pure dice-games. Dicing had a bad reputation (cf. alpha 360, alpha 1899, alpha 2593, alpha 2978, kappa 2592, pi 1384; Toner pp. 95-101), but was defended by others as a harmless relaxation from work and war, if not taken too seriously.
[1] Same or similar glossing in other lexica; see the references at Photius, Lexicon kappa1155 Theodoridis. See LSJ (2) for this noun for a square (literally, quadrilateral). It is worth mentioning that the Latin word for a 6-sided die, tessera, is generally thought to derive from an earlier form of this word, tessera/gwnos (so Breal, cited by Ernout-Meillet). It seems reasonable to assume that this refers to each of the 6 faces of a cubic die, rather than to a mathematical identity between a figure of plane geometry and one of solid geometry.
[2] Each face of a cube may serve as its base. The Greek word ku/kloqen, originally "from a circle", is here used, as often, in the sense of "from all around, on every side". See LSJ.
[3] i.e. Apollodorus the grammarian (alpha 3407). This etymology, also implied in the following sentence, was supported by Boisacq, but is today rejected (e.g. Ernout-Meillet) in favor of the assumption that the word is a loan word. Indeed, the word is sometimes taken in relation to the Anatolian names for the Great Mother, Cybele (see kappa 2586, kappa 2588, kappa 2594), whose image, at least the sacred stone removed in 204 B.C. from Pessinus to the Palatine in Rome, may have been of cubic form (R. Eisler, "Kuba-Kybele," Philologus 68 (1909) 118-151, 161-209, suggesting an etymology from the same root as the sacred Ka'aba in Mecca).
[4] Greek Anthology 5.25.3-4, attributed to Philodemus but perhaps by Meleager [Author, Myth]. The poet talks of the risk of coming to court Cydilla. The phrase of tossing the dice from above his head is probably to be connected to astrological connotations in all gambling, but particularly in board games where the board was designed to represent the sky and motions of heavenly bodies (see tau 7 tabla).
[5] See alpha 2310, epsilon 3013, kappa 1633, kappa 2601, and the discussion at epsilon 695.
[6] See alpha 2310, epsilon 3013.
[7] Polybius fr. 6 Büttner-Wobst, also at alpha 1312, alpha 2273, kappa 894, kappa 2591; cf. epsilon 695 for Polybius 3.94.4 and another passage either from or modelled on Polybius. In the campaigns against Hannibal the Roman general Q. Fabius Cunctator on several occasions chose not to gamble his whole army against the Carthaginian. Both Polybius and Plutarch contrast this successful strategy with the risk-taking of others (M. Minucius in Polybius 3.102-5; Terentius Varro before Cannae in Plutarch, Fabius 14.1). On risk-taking see the cross-references at note [5].