bandstop

This term is a technical specification used primarily in electrical engineering and signal processing. It describes a notch or band-rejection filter that targets a specific frequency range for elimination. While it functions as an adjective to describe the type of filter, it is frequently used as a shorthand noun in professional contexts to refer to the device itself.

In practical application, a bandstop is distinguished from a bandpass filter, which does the exact opposite by allowing only a specific range to pass. It is most commonly employed to remove unwanted noise, such as the 60 Hz hum from power lines, without distorting the rest of the signal spectrum.