sound absorption

A sound absorption barrier is a wall, berm, planting, or other object whose purpose is to prevent or minimize sound transfer from one side to the other side, or bidirectionally between both sides. This is commonly applied to walls alongside highways.

The intended effect is reduced sound passage across the barrier. It can protect one side or limit transmission in both directions.

Walls beside highways are a common example. The definition follows the sound-screening purpose and does not require the barrier to work solely by physical absorption of sound.