To do something furiously means to do it with intense energy, speed, or anger. When a student writes furiously during a timed essay, their pencil flies across the page, racing to finish before time runs out. When a chef chops vegetables furiously, the knife becomes a blur of motion as they work at incredible speed.

The word connects to fury, which is intense anger, so furiously often describes actions powered by strong emotion. A character in a story might pedal furiously to escape danger, or argue furiously with someone who accused them of something unfair. But the word doesn't always involve actual anger: it can simply mean doing something with extreme intensity and speed, like when you scrub furiously at a stubborn stain or study furiously the night before a big test.

Notice how furiously captures both the feeling behind an action and the visible energy it creates. When you see someone working furiously, you can sense their determination or urgency, whether they're building a sandcastle furiously before the tide comes in or furiously searching through their backpack for lost homework.