ground loop definition by Webster's New World
ground loop definition by American Heritage Dictionary
ground loop - Computer Definition
A complete circuit made up of the earth, represented by two different grounding points, and another conductor such as the shield of a cable grounded to devices at both ends. A surge of electricity results in the cable when the grounding points of different devices are at different voltage levels, and the data line connects the devices' ground together. See also ground, surge, and voltage.
A circular path created between the data lines and the ground wires when electronic devices communicate with each other. When systems have earth grounds through different power sources, differences in reference voltages can cause problems for various reasons (see inter-system ground noise). See ground.