What does To have a bee in your bonnet mean?

A bonnet is a type of old-fashioned hat. Imagine what you'd feel like if you had a bee flying around inside your hat, right next to your face! A person with a bee in their bonnet is focused on just one thing - they've got an agenda and they're not going to give up until it's accomplished. Just like if you had an actual bee, you'd be doing everything you could to get it out of your bonnet!