/ ˈtredmɪl; NAmE / noun
1.
[ sing. ] work or a way of life that is boring or tiring because it involves always doing the same things :
I'd like to escape the office treadmill.
2.
[ C ] (especially in the past) a large wheel turned by the weight of people or animals walking on steps around its inside edge, and used to operate machinery
3.
[ C ] an exercise machine that has a moving surface that you can walk or run on while remaining in the same place