Lateran in English

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adj. of or having to do with one of the five general church councils held in the official church of the pope, Church of Saint John Lateran, in Rome.

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Lateran, noun, adjective.

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noun 1. the church of Saint John Lateran, the cathedral church in Rome. The Lateran is the official church of the pope.
2. the palace next to it, once the residence of the popes and now a museum.