Most sources give a variant of the translation "the game is over - all is lost." This is how Shakespeare understood and used it, but perhaps such a dramatic use is best kept to the theater. Today we use it to call someone on their deceit. An obvious parallel is the jig is up. In keeping with the same meaning, most modern sources will translate jig to also mean a game or a joke. A closer look at the etymology of jig reveals an origin from the French giguer for 'to dance' (c. 1560). About a half-century later jig is used to mean a sport or a trick, with 1777 first seeing the use of "the jig is over." Both phrases use up in the sense of meaning finished. Up is often used this way in conjunction with phrases describing time.
Thou wast their nurse; they took thee for
And every day do honour to her grave:
Myself, Belarius, that am Morgan call'd,
They take for natural father. The game is up.
Cymbeline Act III Scene III
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