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Definition of "alveolus" [al•ve•o•lus]

  • A small angular cavity or pit, such as a honeycomb cell. (noun)
  • A tooth socket in the jawbone. (noun)
  • A tiny, thin-walled, capillary-rich sac in the lungs where the exchange of oxygen and carbon dioxide takes place. Also called air sac. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "alveolus" in a sentence
  • "The light from the Proteus penetrated through what seemed to him a vast thickness of tissue and in its muted intensity, the alveolus was a tremendous cavern, with walls that glinted moistly and distantly."
  • "At the end of each bronchiole are tiny sacs called alveoli, each one of them lined with a thin layer of fluid that keeps each alveolus open."
  • "When a fertilized egg is laid by the queen bee in an ordinary alveolus and the larva is fed with standard food, a small, sterile female, a worker bee, is born."