愚笨 is an adjective meaning 'foolish' or 'unintelligent', describing someone lacking in mental sharpness, common sense, or quick understanding. The character 愚 (yú) means 'foolish' or 'dull', often implying a lack of wisdom or judgment, while 笨 (bèn) means 'clumsy' or 'slow-witted', emphasizing slowness in learning or reasoning. Together, they form a compound that intensifies the sense of intellectual deficiency—more formal and slightly more critical than just 笨 alone.

This word is commonly used in written Chinese and formal speech, especially in literary, educational, or evaluative contexts. It carries a mildly negative or disapproving tone, so it’s rarely used self-referentially without irony or humility. While not vulgar, it’s stronger than terms like 迟钝 (chí dùn, 'sluggish') and less harsh than 白痴 (bái chī, 'idiot'). It’s often found in critiques of reasoning, behavior, or decisions—not physical actions.