(1.)Kafir (or kāfir; plural Kuffar, kuffār) is an Arabic word meaning "denier" or "concealer." In a religious context it is often used to mean "infidel," "unbeliever," i.e., a non-Muslim. The noun kufr means "blasphemy, atheism." In the Fiqh, the term amounts to the equivalent of Christian excommunication. The verb, "to declare someone a kafir" is takfir. For example, the novelist Salman Rushdie was declared a kafir in the Fatwa of Ayatollah Khomeini.

(2.)Generally the word kafir means 'unbeliever' and it is not meant as a derogatory label (unless it is used against Muslims by another Muslim).

(3.)Kafir (Arabic: كافر‎ kāfir, plural كفّار kuffār) is an Arabic term used in a Islamic doctrinal sense, usually translated as "unbeliever," "disbeliever," or "infidel." The term refers to a person who rejects God or who hides, denies, or covers the "truth."
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