INFIDEL

adj. heathen, lacking religious faith, showing unbelief

n. one who does not accept a particular religion; one who has no religion, heathen, non-believer

An infidel (literally "one without faith") is an English word meaning "one who doubts or rejects central tenets of a religion or has no religious beliefs", especially in reference to Christianity or Islam. When used in an Islamic sense it serves as a translation of the Arabic word kafir (literally "one who denies the blessings of God") referring to those who deny the existence of God, worship more than one god, or worship something else other than God. "Infidel" and "kafir" are often regarded as offensive.
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Noun
1. a person who does not acknowledge your God
(synonym) heathen, pagan, gentile
(hypernym) nonreligious person
(hyponym) paynim

(n.)
One who does not believe in the prevailing religious faith; especially, one who does not believe in the divine origin and authority of Christianity; a Mohammedan; a heathen; a freethinker.
  

(a.)
Not holding the faith; -- applied esp. to one who does not believe in the inspiration of the Scriptures, and the supernatural origin of Christianity.
  

unfaithful
false
faithless
(d. memorie) = untrustworthy
(d. o traducere) = unfaithful
(d. o traducere) = inaccurate