The term is heavily loaded with religious meaning and used within eschatological contexts. Theologians have debated the identity of the antichrist for centuries.
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Metaphorical use
Can be used metaphorically to describe someone acting against good values. The corrupt leader was seen as an antichrist to the nation's founding principles.
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Cultural sensitivity
Be aware it can offend religious individuals if used flippantly or out of context. Calling a politician the antichrist sparked outrage among the religious community.