1
- a key on a typewriter or computer keyboard used to cause the carriage or cursor to move backwards（打字机或电脑键盘的）退格键, 返回键, 回退键。
2
- mass noun a device on a video recorder or camcorder which produces a slight backward run between shots to eliminate disturbance caused by the interruption of the scanning process（录像机或摄影机上的）返回装置。