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Sunni vs. Shiʿite

Sunni

[soon-ee] / ˈsʊn i /

noun

Islam.

Also called Sunnite. a member of one of the two great religious divisions of Islam, regarding the first four caliphs as legitimate successors of Muhammad and stressing the importance of Sunna as a basis for law.
(used with a plural verb) the Sunni Muslims.

Shiʿite

[shee-ahyt] / ˈʃi aɪt /

Also Shiite,

noun

Islam.

a member of one of the two great religious divisions of Islam that regards Ali, the son-in-law of Muhammad, as the legitimate successor of Muhammad, and disregards the three caliphs who succeeded him.