treadmill

noun

tread·​mill ˈtred-ˌmil 

1

a

: a device having an endless belt on which an individual walks or runs in place for exercise or physiological testing

b

: a mill worked by an animal treading an endless belt

c

: a mill worked by persons treading on steps on the periphery of a wide wheel having a horizontal axis and used formerly in prison punishment

2

: a wearisome or monotonous routine resembling continued activity on a treadmill

the office treadmill

Synonyms of treadmill

• routine
• grind

Examples of treadmill in a Sentence

the treadmill of exhausting family schedules

the treadmill of the morning commute to work

Recent Examples on the Web

Some of the new services offered in South County include electrocardiograms, echocardiograms, ambulatory monitoring patches that track heart rhythm and treadmill stress tests. —Grace Hase, Mercury News, 7 Jan. 2026

For those looking to stay active on vacation, the on-site fitness center is home to Technogym equipment, including treadmills, elliptical machines, and stationary bikes. —Annie Archer, Travel + Leisure, 5 Jan. 2026

Plus, the treadmill’s deck is designed with extra cushioning to help absorb shock. —Izzy Baskette, PEOPLE, 4 Jan. 2026

Hotels will find tricky ways to charge resort fees for a gym with one broken treadmill. —Christopher Elliott, USA Today, 1 Jan. 2026

Word History

First Known Use

1822, in the meaning defined at sense 1c

Rhymes for treadmill

• anthill
• backfill
• bluegill
• crossbill
• distil
• distill
• downhill
• dunghill
• foothill
• fulfil
• fulfill
• goodwill

Kids Definition

treadmill

noun

tread·​mill ˈtred-ˌmil 

1

a

: a device moved by persons treading on steps set around the rim of a wide wheel or by animals walking on an endless belt

b

: a device having an endless belt on which an individual walks or runs in place for exercise or medical testing

2

: a tiring or monotonous routine

Medical Definition

treadmill

noun

tread·​mill ˈtred-ˌmil 

: a device having an endless belt on which an individual walks or runs in place that is used for exercise and in tests of physiological functions see stress test