Marranos were originally Jews living in Iberia who converted or were forced to convert to Christianity, some of whom may have continued to practice Judaism in secret. The term came into later use in 1492 with the Castilian Alhambra Decree, reversing protections originally in the Treaty of Granada (1491).
The converts were also known as cristianos nuevos (Spanish) or cristãos-novos (Portuguese), meaning "New Christians", or conversos (converted ones). In Hebrew the terms anusim ("forced ones") and Zera Yisrael ("seed of [the people of] Israel") are sometimes used.
The term marrano derives from Arabic مُحَرّمٌ muḥarram; meaning "forbidden, anathematized". Marrano in 15th-century Spanish first meant "dirty", "unclean", "swine", "pig", from the ritual prohibition against eating pork, practiced by both Jews and Muslims.
In Portuguese the word marrano (from Spanish) generally refers to "crypto-Jews", although it also means a type of swine (dialectally), "filthy" or "dirty" (sujo), and "outcast" (maldito, excomungado); while the related terms marrão [mɐˈʁɐ̃w] and marrancho [mɐˈʁɐ̃ʃu] mean only the animal: "pig" or "swine".
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