what do you call the reflection of a sound wave?

The reflection of a sound wave is called an echo when you can clearly hear the sound come back after bouncing off a surface.

More generally, when a sound wave hits a surface and bounces back into the same medium, the process is called reflection of sound , and the returned wave is called a reflected sound wave.

Quick Scoop

• When a sound wave hits a wall or cliff and bounces back, that bouncing is the reflection of sound.

• If the reflected sound is heard distinctly after the original (like a repeat of your shout in a canyon), that distinct, returned sound is an echo.

• If many reflections blend together so you don’t hear a clear repeat, the effect is called reverberation (like in a big hall).

In everyday language:

• The phenomenon: reflection of sound.
• The clearly heard “bounce-back” sound: echo.

TL;DR:
You call the reflection of a sound wave an echo when it’s heard as a distinct returned sound; in physics terms, it’s the reflection of sound or a reflected sound wave.

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