treadmill

/ˌtrɛdˈmɪl/

/ˈtrɛdmɪl/

Other forms: treadmills

A treadmill is an exercise machine for walking or running in place. If it's bitterly cold outside, you might decide to go to the gym and run on the treadmill instead of taking your usual outdoor jog.

A treadmill was originally a type of human- or animal-powered machine. By walking on a wheel fitted with steps, a person (or animal) turned it, grinding grain in the process. Treadmills were also used as punishment in prisons where inmates were forced to work. Today the only treadmills you're likely to see are in a gym, but the word is commonly used in a figurative way for any relentless, boring job.

Definitions of treadmill

1. noun

   an exercise device consisting of an endless belt on which a person can walk or jog without changing place
   type of:

   exercise device

   a device designed to provide exercise for the user
2. noun

   a mill that is powered by men or animals walking on a circular belt or climbing steps
   synonyms: tread-wheel, treadwheel

   type of:

   grinder, mill, milling machinery

   machinery that processes materials by grinding or crushing
3. noun

   a job involving drudgery and confinement
   synonyms: salt mine

   type of:

   business, job, line, line of work, occupation

   the principal activity in your life that you do to earn money