1
a
: one of the usually paired compound saccular thoracic organs that constitute the basic respiratory organs of an air-breathing vertebrate
b
: any of various respiratory organs of invertebrates
2
a
: a device enabling individuals abandoning a submarine to rise to the surface
b
: a mechanical device for regularly introducing fresh air into and withdrawing stale air from the lung : respirator compare iron lung

Examples of lung in a Sentence

He filled his lungs with the clean. fresh air.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Road dust is an issue because fine particles generated from traffic can get into residents’ lungs and cause respiratory issues, and the dust also reduces visibility, which can lead to accidents. Nathaniel Warner, The Conversation, 24 July 2026 Five broken vertebrae in his back, broken ribs, a punctured lung, a concussion and injuries to both his shoulder and elbow were littered throughout the medical report. Kansas City Star, 23 July 2026 For instance, the small particles in the smoke can inflame the lungs, trigger coughing and worsen existing health conditions. Jen Reeder, Forbes.com, 23 July 2026 It’s also known for having a variant that can go metastatic, traveling via the bloodstream to invade other organs, particularly the liver, but also the lungs, eyes, and brain. Beth Mole, ArsTechnica, 23 July 2026 See All Example Sentences for lung

Word History

Etymology

Middle English lunge, from Old English lungen; akin to Old High German lungun lung, līhti light in weight — more at light

First Known Use

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

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

Browse Nearby Words

Cite this Entry

“Lung.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lung. Accessed 25 Jul. 2026.

Kids Definition

1
a
: one of the usually paired organs forming the special breathing structure of vertebrates that breathe air
b
: any of various respiratory organs of invertebrates
2
: a device (as an iron lung) to promote breathing and make it easier

Medical Definition

1
a
: one of the usually two compound saccular organs that constitute the basic respiratory organ of air-breathing vertebrates, that normally occupy the entire lateral parts of the thorax and consist essentially of an inverted tree of intricately branched bronchioles communicating with thin-walled terminal alveoli swathed in a network of delicate capillaries where the actual gaseous exchange of respiration takes place, and that in humans are somewhat flattened with a broad base resting against the diaphragm and have the right lung divided into three lobes and the left into two lobes
b
: any of various respiratory organs of invertebrates
2
: a mechanical device for regularly introducing fresh air into and withdrawing stale air from the lungs : respirator see iron lung
lunged adjective

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