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Sunni vs. Shiʿite

[soon-ee] / ˈsʊn i /

noun

Islam.
  1. 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.

  2. (used with a plural verb) the Sunni Muslims.