A person who makes false, damaging statements about someone else; someone who defames or slanders.
From 'defame' plus the agent suffix '-er' (one who does). The person actively spreads false information intended to harm someone's reputation or social standing.
In medieval times, being called a 'defamer' could result in your tongue being cut out or other brutal punishments—societies took reputation-damaging speech so seriously that they invented extreme legal consequences for it.
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