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

The most inventive kill here — set in a school gym, cuing death by treadmill and falling weights — is also the least motivated, but no matter. — Guy Lodge, Variety, 26 July 2026

Using the same tool only to produce more work just builds a faster treadmill. — Terdawn Deboe, Forbes.com, 23 July 2026

The process of creating his footwear involved VO2-max (how much oxygen your body can use during intense exercise) and perception testing, plus a visit to a bespoke facility to run on a treadmill in the race-day spikes. — Liam Tharme, New York Times, 19 July 2026

For indoor workouts, Apple has improved distance tracking on treadmills. — Andrew Gebhart, PC Magazine, 15 July 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