Sonic Scream is the ability to emit sonic waves when screaming.
The human body usually only makes audible sound with the vocal cords and perceives audible sound (20 hZ to 20,000 hZ) using the mechanisms of the ear. A sonic screamer is able to generate sonic energy on a much more precise and powerful scale. This may involve a more advanced set of vocal cords, or an entirely separate set of organs that generate vibrations. Their ears are usually similarly adapted to cope with the generated energy.