Final answer:
African Yoruba spirits synchronized with Roman Catholic saints in the new world are known as Orishas, which are central to the syncretic religion Santeria, widely practiced in Cuba.
Step-by-step explanation:
African Yoruba spirits whose names are used in conjunction with Roman Catholic saints in the new world are known as Orishas. This syncretism can notably be observed in religions such as Santeria and Vodou. In Santeria, the religion which is popular in Cuba and has a significant African influence, African-based spirits are overlaid with Catholic saints. This practice arose as a means for enslaved Africans in the New World to retain their traditional beliefs while outwardly appearing to follow Christianity. The Santeria religion is estimated to be practiced by 70 percent of Cubans, integrating rituals, practices, and deities from the Yoruba people into a framework that aligns with the Catholic faith.