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n. Either of two spongy, saclike respiratory organs in most vertebrates, occupying the chest cavity together with the heart and functioning to remove carbon dioxide from the blood and provide it with oxygen.

n. A similar organ in some invertebrates, including spiders and terrestrial snails.

idiom. at the top of (one's) lungs As loudly as one's voice will allow.

n. A biological organ that extracts oxygen from the air.

n. An organ for aërial respiration; -- commonly in the plural.

n. One of the two spongy or saccular organs, occupying the thorax or upper part of the body-cavity, which communicate with the pharynx through the trachea, and are the organs of respiration in air-breathing vertebrates.

n. In entomology, one of the respiratory organs peculiar to those Arachnida whose tracheal system is modified into a number of lamellæ superimposed upon one another like the leaves of a book. They are also called pulmonary lamellæ and respiratory leaflets.

n. In pulmonate mollusks, a modification of the integument subserving aërial respiration: more fully called external lung. Huxley.

n. plural A bellows-blower; a chemist's servant.

n. either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood

"Amniotic fluid is an important prognostic indicator because a critical phase in lung development occurs around 18 to 20 weeks of gestation."

lungs   

respiratory organ   

miners' lung    grinders'    to try one's lungs    lung suction mask    brown induration of the lungs    black lung    at the top of one's lungs    collier's lung   

lungement   

breather    lights    pulmonary    pulmonal    pulmonic    bellows    archaic    or    informal    italbrac   

Sung    Young    among    bung    clung    dung    flung    fung    hung    overhung   

Liver    stomach    bladder    brain    tissue    intestine    organ    throat    gland    muscle