Cleverness, shrewdness, or cunning in thought or action.
From Latin 'astutus' (clever, shrewd), this noun form adds the suffix '-ity' to express the quality of being mentally sharp or crafty, dating back to medieval Latin usage.
The word 'astute' comes from the same root, and it originally meant 'having keen perception'—the idea being that a shrewd person can see things others miss, like having sharper senses.
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