infidel
noun /ˈɪnfɪdəl/, /ˈɪnfɪdel/
/ˈɪnfɪdəl/, /ˈɪnfɪdel/
(old use, offensive)- an offensive way of referring to somebody who does not believe in what the speaker considers to be the true religionWord Originlate 15th cent.: from French infidèle or Latin infidelis, from in- ‘not’ + fidelis ‘faithful’ (from fides ‘faith’, related to fidere ‘to trust’). The word originally denoted a person of a religion other than one's own, specifically a Muslim (to a Christian), a Christian (to a Muslim), or a Gentile (to a Jew).