弄臣（中国古称优，原作演员解），是古代宫廷中以插科打诨来为国王消烦解闷的人物（但未必是正式的职衔），常由侏儒担任。

虽然身分卑下，但弄臣往往是宫廷中唯一享有言论自由的人(all-licensed fool)，文学、传说中他们常被塑造成「谈言微中，亦可以解纷」的讽谏者，例如莎剧里的一众弄人，以及《史记·滑稽列传》里记述的优孟和优旃，他们常利用了滑稽的讽刺功能对君王进行谏言。

国王与弄臣的关系有时亲密得令人难以置信，亨利八世与他的弄臣萨默斯（Will Sommers）是有名的例子，据说萨默斯跟国王亲密得可以直呼其名，管他叫「哈里」（Harry）、「大叔」（Uncle）。在《一千零一夜·驼背人的故事》中，那个中国皇帝少见他的弄人「一霎眼的时间」也是不能的。欧阳修《新五代史·伶官传》记载，后唐甚至有够胆打皇帝耳光的弄臣：

A jester, court jester or fool was historically an entertainer during the medieval and Renaissance eras who was a member of the household of a nobleman employed to entertain him and his guests. A jester was also an itinerant performer who entertained common folk at fairs and markets. Jesters are also modern day entertainers who resemble their historical counterparts. Jesters in medieval times are often thought to have worn brightly coloured clothes and eccentric hats in a motley pattern and their modern counterparts usually mimic this costume. In medieval times jesters entertained with a wide variety of skills: principal ones included songs, music, and storytelling; additional ones included acrobatics, juggling, telling jokes, and magic. Much of the entertainment was performed in a comic style and many jesters made contemporary jokes in word or song about people or events well known to their audiences.