Loudly means doing something in a way that makes a lot of noise or can be heard from far away. When you speak loudly, your voice carries across the room. When someone laughs loudly, everyone nearby hears it. When a door slams loudly, it makes a sharp bang that startles people.

The word describes the volume or intensity of sound. A teacher might ask students to read loudly so the whole class can hear, or remind them not to talk too loudly during quiet work time. A marching band plays loudly so crowds can hear the music, while librarians speak softly because libraries aren't meant to be loud places.

Loudly can also describe actions that draw attention, even beyond just sound. Someone might dress loudly by wearing very bright, clashing colors that make everyone notice them. In this sense, loudly suggests being bold, obvious, or impossible to ignore, whether that's through actual noise or by standing out in other ways.