A person who dishonors someone or something; one who brings shame or disgrace to another.
From 'dishonor' (dis- + honor) plus the agent suffix '-er' (from Old English '-ere'). This occupational or descriptive noun identifies someone who performs the action of dishonoring.
Adding '-er' to create agent nouns is one of English's most productive patterns—a 'dishonorer' sounds almost formal enough to be a job title, which shows how the suffix works even for negative actions.
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