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lung

(lŭng)

1. Either of two spongy, saclike respiratory organs in air-breathing vertebrates, occupying the chest cavity together with the heart and functioning to provide oxygen to the blood while removing carbon dioxide.

2. 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.

[Middle English lunge, from Old English lungen, lungs; see leg^wh- in the Appendix of Indo-European roots.]

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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