lung
Americannoun
-
either of the two saclike respiratory organs in the thorax of humans and the higher vertebrates.
-
an analogous organ in certain invertebrates, as arachnids or terrestrial gastropods.
idioms
noun
-
either one of a pair of spongy saclike respiratory organs within the thorax of higher vertebrates, which oxygenate the blood and remove its carbon dioxide
-
any similar or analogous organ in other vertebrates or in invertebrates
-
in one's loudest voice; yelling
-
Either of two spongy organs in the chest of air-breathing vertebrate animals that serve as the organs of gas exchange. Blood flowing through the lungs picks up oxygen from inhaled air and releases carbon dioxide, which is exhaled. Air enters and leaves the lungs through the bronchial tubes.
-
A similar organ found in some invertebrates.
Other Word Forms
Etymology
Origin of lung
before 1000; Middle English lungen, Old English; cognate with German Lunge; akin to light 2, lights
Explanation
A lung is an internal organ that makes it possible for you to breathe. Your lungs remove carbon dioxide from your body while sending oxygen into your blood stream. All vertebrates — animals with a spinal column — have lungs. Humans have two of them, and they're what makes your chest rise and fall as you breathe in and out. They're also the organs that keep you breathing, and therefore alive. Lung, by way of the Old English lungen, comes from an Indo-European root that literally means "the light organ."
Vocabulary lists containing lung
Animals (Zoology) - Introductory
Looking to grow your vocabulary? Check out this interactive, curated word list from our team of English language specialists at Vocabulary.com – one of over 17,000 lists we've built to help learners worldwide!
Human Anatomy and Physiology - Introductory
Interested in learning more words like this one? Our team at Vocabulary.com has got you covered! You can review flashcards, quiz yourself, practice spelling, and more – and it's all completely free to use!
Human Anatomy and Physiology - High School
Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Still, the data suggest that contracting hantavirus is rare, said Dr. Afif El-Hasan, member of the American Lung Assn.’s national board of directors.
From Los Angeles Times • May 7, 2026
A 2021 study from the Epidemiology of Young Lung Cancer Project, the Genomics of Young Lung Cancer Project, showed that lung cancer subtypes in people under 40 differ from those seen in older adults.
From Science Daily • Apr. 17, 2026
The Melanoma Lung & liver cavity cancer will mean I will…
From Los Angeles Times • Apr. 13, 2026
Their findings, published in Nature Communications, come from a study titled "Lack of Caspase 8 Directs Neuronal Progenitor-like reprogramming and Small Cell Lung Cancer Progression."
From Science Daily • Mar. 25, 2026
Now Wang Lung in the old days when the great family were there would have felt himself one of these common people and against the great and half hating, half fearful of them.
From "The Good Earth" by Pearl S. Buck
![]()
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.