What is "the die is cast"

Die \Die\, n.; pl. in 1 and (usually) in 2, Dice (d[=i]s); in 4 & 5, Dies (d[=i]z). [OE. dee, die, F. d['e], fr. L. datus given, thrown, p. p. of dare to give, throw. See Date a point of time.]

1. A small cube, marked on its faces with spots from one to six, and used in playing games by being shaken in a box and thrown from it. See Dice.

2. Any small cubical or square body.

   Words . . . pasted upon little flat tablets or dies.
   --Watts.

3. That which is, or might be, determined, by a throw of the die; hazard; chance.

   Such is the die of war.
   --Spenser.

4. (Arch.) That part of a pedestal included between base and cornice; the dado.

5. (Mach.)

   1. A metal or plate (often one of a pair) so cut or shaped as to give a certain desired form to, or impress any desired device on, an object or surface, by pressure or by a blow; used in forging metals, coining, striking up sheet metal, etc.

   2. A perforated block, commonly of hardened steel used in connection with a punch, for punching holes, as through plates, or blanks from plates, or for forming cups or capsules, as from sheet metal, by drawing.

   3. A hollow internally threaded screw-cutting tool, made in one piece or composed of several parts, for forming screw threads on bolts, etc.; one of the separate parts which make up such a tool.

      Cutting die (Mech.), a thin, deep steel frame, sharpened to a cutting edge, for cutting out articles from leather, cloth, paper, etc.

      The die is cast, the hazard must be run; the step is taken, and it is too late to draw back; the last chance is taken.

phr. (context idiomatic English) The future is determined; there are no more options; events will proceed in an irreversible manner; the point of no return has been passed.

__NOTOC__ "The Die Is Cast" is the 67th episode of the television series Star Trek: Deep Space Nine, the 21st episode of the third season. It concludes the story begun in the previous episode, " Improbable Cause".

Garak has to interrogate Odo to prove his loyalty to his former mentor as a Tal Shiar – Obsidian Order attack on the Founders is underway.