treadmill
noun uk/ˈtred.mɪl/ us/ˈtred.mɪl/
(REPEATED WORK)
[ S ]繁重无聊的重复性工作
any type of repeated work that is boring and makes you feel tired and seems to have no positive effect and no end
There were days when having kids seemed like an endless treadmill of feeding, washing, and nappy-changing. 过去养育孩子似乎就是永无休止的喂饭、洗衣和换尿布，繁重而又单调。
(EXERCISE MACHINE)
[ C ]（锻炼用的）踏步机，跑步机
an exercise machine that consists of a moving strip or two step-like parts on which you walk without moving forward
(WHEEL)
[ C ]（过去通常用以惩罚犯人的）踏车
a wide wheel turned by the weight of people climbing on steps around its edge, used in the past to provide power for machines or, more usually, as a punishment for prisoners