A man whose wife is unfaithful; a cuckold, a term historically used in Romance languages with connotations of shame.
From Italian cornuto or Spanish cornudo, derived from Latin cornūtus (horned). The term entered English from Romance languages, carrying the symbolic association of horns with cuckolded men.
The insult 'cornuto' is so old it goes back to when horns symbolized the devil and deception—calling a man cornuto was saying both his wife cheated AND that he was foolish enough to be tricked, a double shame.
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