Rubicon

The Rubicon was a river in Italy on Earth.

When a new runabout was assigned to Deep Space 9 in late 2371 as a replacement for the USS Mekong, Commander Benjamin Sisko suggested the name USS Rubicon for it, to which Major Kira Nerys remarked that at the rate they went through runabouts it was a good thing Earth had so many rivers. (DS9: "Family Business")

The phrase "crossing the Rubicon" means passing a point of no return, which refers to Julius Caesar crossing the river to start a civil war in Rome. The title of the Star Trek: Discovery episode "Rubicon" is a reference to this phrase and the title of the Star Trek: Deep Space Nine episode "The Die is Cast" refers to a phrase said to be uttered by Caesar while crossing the Rubicon.

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