Superlative form of cunning: most cunning.(adjective)
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Use "cunningest" in a sentence
"Withal, as if to wear the time, Birdalone betook her diligently to her needlework, and fell to the cunningest of broidery; so that"
"Apollo and to Artemis, our Lady of the Chase,202 to share with them the produce of spoil, he lets slip a single hound, the cunningest at scenting of the pack."
"For you are to know that trout be now scarce and whereas he was ever a fearful fish, he hath of late become so wary that none but the cunningest anglers may be even with him."