顽皮在英语中的翻译是"mischievous"或"naughty". 来源：这个词来源于古英语中的"nawht"，意思是"恶作剧"或"淘气". 例句：

He is such a mischievous boy, always playing tricks on his friends. (他是个顽皮的男孩，总是捉弄他的朋友们。)

She has a naughty smile on her face, indicating that she is up to something. (她脸上带着一个顽皮的笑容，表明她正在做什么事情。)