I think both of them are inaccuracy.In my eyes,it should mean that a kid who is very active and naughty.However,when someone older than you and they want to show that their experience is more abundant than you on something,they can call you that.

A dialect in China, it means little child.

这不只是简单在称呼一个小孩子的，它的重点在于：强调被称呼的人是一个无知、楞头楞脑的小孩子。

Usually it‘s used for calling a child.

Just like"hey,kids"