One is arrogant and egotistical
, and believes they are superior to others, for a reason that is petty, a reason that is questionable or based on opinion, or for being in a 'better' situation than others placed entirely on luck and not one's actual experiences (such as a parent's wealth).
As a result, they are prejudiced to those that they consider to be less 'elite'. To those that are of equal or higher status, they will either show more respect to, or envy.
Brandon is an elitist bastard, because he believes his desktop screenshot is better than anybody elses and makes fun of others because of it.