1.NounThe range through which an input can be varied without initiating an observable response. Deadband is usually expressed in percent of span.
"The thermostat was errantly set with a deadband from 18°C to 27°C, causing the air conditioner to not turn on below 27°C, and the heater to not come on above 18°C."
2.NounIn the domain of a transfer function, the band of input values where the output is zero. "(the output is 'dead' - no action occurs)"
"The game will not respond to small movements of the joystick, until the stick is pushed out of its dead zone."
3.NounBacklash in a mechanical system.
"The steering system has so much backlash that it takes a full rotation of the wheel to exit its deadband and affect the steering."