n
1 mill-wheel turned by the weight of people or animals treading on steps round its inside edge (formerly worked by prisoners as a punishment) （人力或畜力的）踏车（旧时用以惩治囚犯）.
2 (fig 比喻) tiring or monotonous routine work; drudgery 累人的或单调的例行工作; 繁重乏味的工作
*I can't get off the office treadmill. 我无法摆脱单调的坐班工作.

n

[C]
a piece of exercise equipment that has a large belt around a set of wheels, that you can walk or run on while staying in the same place
[singular]
work or a way of life that seems very boring because you always have to do the same things
　the treadmill of working in the office
[C]
a mill worked in the past by prisoners treading on steps fixed to a very large wheel