A person who treats others with contempt or shows extreme disrespect.
From contemn (to scorn) plus -er (agent suffix indicating one who does something). This follows the English pattern of adding -er to verbs to create nouns for people who perform those actions.
Medieval and Renaissance literature frequently used this term to describe villains or antagonists—someone who contemns others is fundamentally rejecting their worth as a human being, which was considered one of the gravest moral failures.
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