A false and malicious statement designed to injure someone's reputation; slander. The act of making such false statements about someone.
From Latin 'calumnia' meaning false accusation, trickery, from 'calvi' (to deceive). The word entered English in the 15th century through Old French, retaining its sense of deliberate deception to harm reputation.
Think 'calamity' - calumny causes a calamity for someone's reputation! Both words start with 'cal' and both cause serious damage, just to different things.
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