A reflected sound wave is called an echo. An echo occurs when sound waves bounce off a surface and return to the listener after a brief delay.
When you shout in a canyon or a large empty room, your voice travels through the air until it hits a solid surface, like a wall or the rocky sides of a canyon. The sound wave then reflects back to you, allowing you to hear your voice again. The time it takes for the sound to travel to the surface and back determines how far away that surface is.
This phenomenon is not only interesting but also has practical applications. Echoes are used in various fields, such as underwater sonar technology for locating objects, medical imaging with ultrasound, and even in architectural design to improve sound quality in venues.