Hunger is the uncomfortable physical feeling you get when your body needs food. Your stomach might feel empty or even hurt, you might feel weak or tired, and food becomes all you can think about. When you skip breakfast and your stomach starts growling by lunchtime, that's hunger telling you it's time to eat.

The word also describes a strong desire or craving for something beyond food. Someone might have a hunger for knowledge, reading every book they can find about ancient Egypt or space exploration. An athlete might have a hunger to win, practicing harder than anyone else on the team. A hunger for adventure drives explorers to climb mountains or sail across oceans.

Throughout history, hunger has been one of humanity's greatest challenges. Millions of people around the world still struggle with severe hunger every day, not knowing where their next meal will come from. When people face constant hunger over long periods, it's called starvation, a dangerous condition that weakens the body and can make people sick.