Devilish describes something mischievous, cunning, or wickedly clever. When your little brother flashes a devilish grin before hiding your homework, you know he's up to no good. A devilish plan might be sneaky but clever, like figuring out how to convince your parents to extend bedtime by offering to do extra chores.

The word suggests playful trouble rather than serious harm. A devilish sense of humor finds amusement in harmless pranks and clever tricks. Someone might devise a devilish strategy in chess that traps their opponent in an unexpected way, or a mystery novelist might create a devilish plot twist that surprises every reader.

The word can also describe something extremely difficult or challenging. A math problem might be devilishly hard if it requires extraordinary cleverness to solve. When something is devilishly tricky, it tests your skills and patience in frustrating ways.

While the word connects to “devil,” it rarely means truly evil in everyday use. Instead, it captures that quality of being sly, impish, and just a bit naughty. Think of it as the difference between a troublemaker who enjoys outsmarting others for fun and someone who genuinely wants to hurt people.