Salim, Kafir is a "rejecter". In the Islamic doctrinal sense the term refers to a person who does not recognize God (Allah) or the prophethood of Muhammad (i.e., any non-Muslim) or who hides, denies, or covers the truth. In cultural terms, it is seen as a derogatory term used to describe an unbeliever, non-Muslims, apostate from Islam and even between Muslims of different sects. It is usually translated into English as "infidel" or "unbeliever."
What do you conclude reading the definition above? Kafir has been used as a derogatory term throughout the history by Muslims.
