|1.||a stream in N Italy: in ancient times the boundary between Italy and Cisalpine Gaul. By leading his army across it and marching on Rome in 49 |
|2.||(sometimes not capital) a point of no return|
|3.||a penalty in piquet by which the score of a player who fails to reach 100 points in six hands is added to his opponent's|
|4.||cross the Rubicon, pass the Rubicon to commit oneself irrevocably to some course of action|
A river in northern Italy that Julius Caesar crossed with his army, in violation of the orders of the leaders in Rome, who feared his power. A civil war followed, in which Caesar emerged as ruler of Rome. Caesar is supposed to have said, “The die is cast” (referring to a roll of dice), as he crossed the river.
Note: “Crossing the Rubicon” is a general expression for taking a dangerous, decisive, and irreversible step.
cross the Rubicon
Irrevocably commit to a course of action, make a fateful and final decision. For example, Once he submitted his resignation, he had crossed the Rubicon. This phrase alludes to Julius Caesar's crossing the Rubicon River (between Italy and Gaul) in 49 b.c., thereby starting a war against Pompey and the Roman Senate. Recounted in Plutarch's Lives: Julius Caesar (c. a.d. 110), the crossing gave rise to the figurative English usage by the early 1600s.