A fist is what you make when you curl your fingers tightly into your palm and fold your thumb over them, creating a compact ball with your hand. People make fists for different reasons: a boxer makes fists to punch, a baby makes fists when concentrating hard on something, and you might clench your fists when you're frustrated or determined.

The word often appears in expressions that reveal emotions or attitudes. A fist pump celebrates victory or excitement. When someone shakes their fist at something, they're showing anger. If you hold something in your fist, you're gripping it tightly.

Fists also symbolize power, unity, or resistance. Workers raising fists together show solidarity. A firm fist or iron fist describes strict, powerful control, like when people say a ruler governs with an iron fist.

In anatomy, your fist is roughly the size of your own heart, which is why doctors sometimes use it as a measuring comparison. And while fists are often associated with fighting, they can also express determination, like when an athlete pumps their fist after crossing the finish line to show the strength and effort that got them there.