People who don't believe in a particular religion, especially one seen as the 'true' faith by those using the term.
From Latin 'infidelis' (in- 'not' + fidelis 'faithful'), meaning not believing in faith, used historically by religious groups to describe those outside their beliefs.
The word 'infidel' reveals something fascinating about how religions see themselves—each religion originally used it to describe non-believers, showing that perspective matters entirely depending on which group is doing the labeling.
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