Wily means clever in a sneaky or cunning way. A wily person knows how to get what they want through smart tricks and careful planning. Think of a fox in a fable who outsmarts the farmer by digging under the fence at night instead of trying to break through it. That's wily behavior: smart, strategic, and a little bit sneaky.

The word often describes someone who's been around long enough to learn all the angles. A wily chess player doesn't just know the rules; she knows exactly how to bait her opponent into making mistakes. A wily negotiator might ask for something big first, knowing you'll feel relieved when he “settles” for what he actually wanted all along.

Wily isn't quite the same as dishonest. A wily character in a story might be one of the good guys who uses clever tricks to outsmart the villain. But it does suggest someone who's calculating and strategic, someone who thinks three steps ahead. When Odysseus escaped the Cyclops by hiding under sheep and calling himself “Nobody,” that was wily thinking. The word captures that mixture of intelligence, experience, and craftiness that makes someone very hard to fool or defeat.