1.
If you describe someone as ~, you mean that they do not know things they should know. If someone is ~ of a fact, they do not know it.
People don’t like to ask questions for fear of appearing ~...
ADJ: oft ADJ of/about n
2.
People are sometimes described as ~ when they do something that is not polite or kind. Some people think that it is not correct to use ~ with this meaning.
ADJ