In Chinese culture, direct confrontation is often avoided. As a result, insults can be graded with much subtlety. `呆子` sits on the milder end of the spectrum. It's not a deeply offensive curse word but rather an observation of someone's perceived lack of social grace or quick thinking. A key cultural point is its frequent use as a term of endearment, especially in romantic relationships. A girlfriend might call her boyfriend a `呆子` after he does something endearingly clumsy or fails to understand her subtle hints. In this way, it's very different from the English “idiot,” which is almost always negative. A better Western comparison for this affectionate usage might be “goofball,” “silly,” or the slightly old-fashioned “lunkhead.” This duality is critical. The term plays into a cultural archetype found in classic Chinese literature, like the character 郭靖 (Guō Jìng) from The Legend of the Condor Heroes. Guo Jing is honest, loyal, and incredibly powerful, but he is famously a `呆子`—slow-witted, naive, and straightforward to a fault. He is beloved precisely because of this quality, not in spite of it. This shows that being a `呆子` isn't always a bad thing; it can imply a certain purity or lack of cunning that is seen as virtuous.
How you hear `呆子` used today depends almost entirely on the relationship between the speaker and the listener.