1. A person (usually male) who engages in acts that put his feelings or rights above those of others. However, the degree of asshole this person is depends entirely on whether the person concerned realizes that he is an asshole or not.
2. A word typically used by females in attempt to make their male partner feel guilty about something he should not feel guilty about.
1. Moll: Tom and Dick are both assholes! Why'd you wanna fuck with Tom instead?
Nell: Cos Dick is an asshole and he knows it!
2. Why did you fuck her you asshole? Didn't you know that next week would be the first time we were ever gonna meet?
An asshole is arrogant, abrasive and smart, but he is not disingenuous. He may be fully aware that he is an asshole and he may take pride in it.
Bill Maher is an asshole.