Hubris
/ˈhjuː.brɪs/ noun mediumExcessive pride or self-confidence, especially of a kind that leads to a downfall.
The champion's hubris led him to skip training for the rematch, and he lost in the first round.
Memory Trick
Hubris sounds like 'you-bris(k)' — walking around brisk and cocky with your chin up, until pride brings you crashing down.