- a person who does not believe in a particular religion, esp. the prevailing religion; specif.,: now often a disparaging term, but still used descriptively as within historical contexts
- among Christians, a non-Christian
- among Muslims, a non-Muslim
- a person who holds no religious belief
- a person who does not accept some particular theory, belief, etc.
Origin of infidelMiddle English from Middle French infidèle from Classical Latin infidelis, unfaithful (in LL(Ec), unbelieving) from in-, in- + fidelis: see fidelity
- that is an infidel; unbelieving
- of infidels