treadmill
nounUK /ˈtrɛd.mɪl/
US /ˈtrɛd.mɪl/
A machine you walk or run on to get exercise without going anywhere.
She runs on the treadmill for thirty minutes every morning.
OTHER MEANINGS
2. A boring routine that never changes or gets better.
He felt stuck on a treadmill of long hours and low pay.
3. A wheel turned by people or animals walking on its steps, once used to power mills.
In the old mill, a dog ran inside a treadmill to turn the grinding stone.
4. Any job or situation that keeps you busy but gets you nowhere.
Endless meetings became a treadmill that left no time for real work.