cross the Rubicon

cross the Rubicon

Fig. to do something that inevitably commits one to following a certain course of action. (Alludes to the crossing of the River Rubicon by Julius Caesar with his army, which involved him in a civil war in B.C. 49.) Jane crossed the Rubicon by signing the contract. Find another job before you cross the Rubicon and resign from this one.

See also: cross

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cross the Rubicon  (formal)

to do something which will have very important results, which cannot be changed later

Usage notes: Julius Caesar started a war by crossing the river Rubicon in Italy.

International pressure may be able to prevent the country crossing the Rubicon to authoritarian rule.

See also: cross

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cross the Rubicon (slightly formal)

to make a decision that cannot be changed later When I quit editing and decided to be a writer, I had crossed the Rubicon to an uncertain future.

Etymology: based on Julius Caesar's crossing of the Rubicon River in 49 B.C.E., which began a war

See also: cross