The word 傻瓜 is literally "foolish melon", and its formation originates from a specific historical and cultural association rather than a grammatical rule. During the Qing Dynasty, a region called 瓜子店 was known for its hardworking but stereotypically simple and gullible melon farmers. Over time, people from this region were mockingly called 傻瓜, using "melon" (瓜) as a metonym for the people themselves. The term eventually shed its specific geographic link, and the character 瓜 absorbed the connotation of simplicity and stupidity, permanently fusing with 傻 (foolish) to form the common insult for a fool or idiot.