Definition of Rosetta stone
1 : a black basalt stone found in 1799 that bears an inscription in hieroglyphics, demotic characters, and Greek and is celebrated for having given the first clue to the decipherment of Egyptian hieroglyphics
2 : one that gives a clue to understanding
Origin of rosetta stone
First Known Use: 1822
Rhymes with rosetta stone
Learn More about rosetta stone
Britannica.com: Encyclopedia article about "Rosetta stone"
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