Noblesse oblige is the idea that if you’re of noble birth or basically super rich, it’s your duty act right and help others. It’s French for the “nobility obliges.” So, trust fund kids, get thee to the soup kitchen!
The concept of noblesse oblige has been around much longer than the actual phrase, which was first recorded in English in 1837. As long ago as ancient Greece, aristocrats have mulled over their obligations to society. While the result of noblesse oblige can be positive, historically it's been used to justify the privilege of wealthy and powerful people. Now, sometimes people refer to noblesse oblige in a sassy, ironic way.