Morally evil, wicked, or of poor quality; despicable and worthy of disgust.
From Latin 'vilis' (cheap, worthless, base). The word entered English through Old French and has meant morally base or worthless since the 1200s.
In ancient Rome, 'vilis' literally meant 'cheap' or 'worthless' in price—over time, they connected cheapness of value with moral worthlessness, which tells us something about how societies think.
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