According to Robert I. Sutton, an Asshole is someone who uses their power to treat others like dirt. The definition is as follows - After talking to the alleged asshole, does the “target” feel oppressed, humiliated, de-energized, or belittled by the person? In particular, does the target feel worse about him- or herself?
I am relying on Robert I. Sutton's help to get through a rough patch in my office. If you are going to improve, then you need to ask uncomfortable questions.