Superlative form of cunning; the most clever, sly, or strategic (often in a deceptive way).
From 'cunning' plus the superlative suffix '-est,' following older English superlative patterns, as most modern speakers prefer 'most cunning.'
Shakespeare and medieval writers used 'cunningest' freely, but modern English largely switched to 'most cunning'—another casualty of English's shift from inflectional to analytical forms!
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