bellows

noun

bel·​lows ˈbe-(ˌ)lōz How to pronounce bellows (audio)
-ləz
plural in form but singular or plural in construction
1
: an instrument or machine that by alternate expansion and contraction draws in air through a valve or orifice and expels it through a tube
also : any of various other blowers
2
: lungs
3
: the pleated expansible part in a camera
also : a metallic or plastic flexible and expansible vessel

Word History

Etymology

Middle English bely, below, belwes — more at belly

First Known Use

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of bellows was before the 12th century

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Cite this Entry

“Bellows.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/bellows. Accessed 10 Sep. 2025.

Kids Definition

bellows

singular or plural noun
bel·​lows ˈbel-ōz How to pronounce bellows (audio)
-əz
1
: a device that produces a strong current of air when it is spread apart and then pressed together
2
: a part of some cameras that is pleated and can expand

Medical Definition

bellows

noun, plural in form but singular or plural in construction
bel·​lows ˈbel-(ˌ)ōz, -əz How to pronounce bellows (audio)
: lungs

Biographical Definition

Bellows

biographical name

Bel·​lows ˈbe-(ˌ)lōz How to pronounce Bellows (audio)
George Wesley 1882–1925 American painter

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