treadmill
[noun]
Synonyms: routine, grind, groove, pace, rote, rut

[TahlilGaran] English Synonym Dictionary ▲

tread‧mill /ˈtredˌmɪl/ noun

1. [countable] 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

2. [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

3. [countable] a mill worked in the past by prisoners treading on steps fixed to a very large wheel

[TahlilGaran] Dictionary of Contemporary English ▲