Clipping

Refers to a type of distortion that occurs when an amplifier is driven into an overload condition. Usually the "clipped" waveform contains an excess of high-frequency energy.

The sound becomes hard and edgy.

On an oscilloscope clipping appears to flatten the tops and/or bottoms of the wave forms as if someone took a pair of scissors and "clipped or cut" the top and bottom of the wave.

See also: Clipper Circuit, Harmonic, Headroom.