An adjective used to describe someone who is extremely arrogant and/or overbearing, with grandiose ideas about themselves, but little clue as to how ridiculous and self-inflated they look.
Taken from the Cardassian race from Deep Space 9.
Guy 1: God, Fletcher Daniels is such a Cardassian.
Guy 2: I know. Did you see him hitting on Patsy? What a dick.