What does big silly girl mean?

This is not a real dirty word. Some people like to tell jokes, people with a good sense of humor like to call women silly girls, while some people have a good impression on this woman and also call her silly girl.

Perhaps some local dialects have other meanings, for example, this woman is a little slow and incoherent, and some people call such a woman a silly girl. No matter what you call it, it is better to respect each other and be polite to each other.