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.
Mercury is toxic to the nervous, digestive and immune systems, as well as the kidneys, lungs and skin, according to the World Health Organization. — Sandee Lamotte, CNN Money, 2 Oct. 2026 Over 100 years ago, French scientists developed a vaccine for tuberculosis, a lung infection that still kills over 1 million people each year, 80% of them in low- and middle-income countries. — Joshua R. Ehrlich, The Conversation, 1 Oct. 2026 Rantzen was diagnosed with terminal lung cancer in 2023 and went on to become a prominent campaigner for legalizing assisted dying in the UK. — Jake Kanter, Deadline, 30 Sep. 2026 That evening, the complaint says, Ramirez died of heart and lung failure caused by heat exposure. — ABC News, 30 Sep. 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 3 Oct. 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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