hubris noun [from the Greek hybris]
exaggerated self pride, arrogance or self-confidence, often resulting in fatal retribution.
In ancient Greece, "hubris" referred to actions taken to shame and humiliate a victim, thereby making oneself seem superior. It was considered the greatest sin of the ancient Greek world. The meaning was further generalized in its modern English usage to apply to any outrageous act or exhibition of pride or disregard for basic moral law.
"During his long tenure in the financial world, Friedman has watched dozens of his competitors' businesses killed by hubris born of success rather than by unsound business decisions or adverse market conditions."
-- Lisa Endlich, Goldman Sachs: The Culture of Success.