lung

American  

[luhng] / lʌŋ /

noun

1. either of the two saclike respiratory organs in the thorax of humans and the higher vertebrates.

2. an analogous organ in certain invertebrates, as arachnids or terrestrial gastropods.

---

idioms

1. at the top of one's lungs, as loudly as possible; with full voice.

   The baby cried at the top of his lungs.

lung British  

/ lʌŋ /

noun

1. 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

2. any similar or analogous organ in other vertebrates or in invertebrates

3. in one's loudest voice; yelling

---

lung Scientific  

/ lŭng /

1. 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.

2. A similar organ found in some invertebrates.

---

lung More Idioms  

1. see at the top of one's lungs.

---

Other Word Forms

• half-lunged
  adjective
• lunged
  adjective

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."

Example Sentences

To better understand this trend, scientists launched the Epidemiology of Young Lung Cancer Project.

From Science Daily • Apr. 17, 2026

He had a cameo in Iron Lung, the smash-hit horror film self-financed, filmed and directed by fellow social media star Markiplier.

From BBC • Apr. 14, 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

Wang Lung leaned down to him and said loudly in his ear, “Here am I and I will buy you a coffin second to my father’s only!”

From "The Good Earth" by Pearl S. Buck