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Great Schism

American  

noun

  1. a period of division in the Roman Catholic Church, 1378–1417, over papal succession, during which there were two, or sometimes three, claimants to the papal office.

Great Schism British  

noun

  1. the breach between the Eastern and Western churches, usually dated from 1054

  2. the division within the Roman Catholic Church from 1378 to 1429, during which rival popes reigned at Rome and Avignon

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