a sac containing air.
any of certain cavities in a bird's body connected with the lungs.
a saclike dilation of the wall of a trachea in many insects.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
How to use air sac in a sentence
During intense exercise, the heart can become overworked, which may lead to some fluid buildup in the small air sacs of the lungs, known as pulmonary edema, a condition commonly connected to heart problems.Do you sometimes taste blood when working out? Here’s what might be happening. | Allyson Chiu | October 8, 2021 | Washington Post
The virus invades the lining of the lungs, including the alveoli, tiny air sacs that capture oxygen from each breath and quickly pass it into the bloodstream.
Pneumonia occurs when “air sacs in the lungs fill with fluid, limiting their ability to take in oxygen and causing shortness of breath, cough and other symptoms,” Galiatsatos writes.
ARDS occurs when air sacs become filled with fluid leaking from the tiny blood vessels in the lungs, causing the lungs to fail.
But the joints of the backbone in front of the sacrum receive their air from the cervical air sac.Dragons of the Air | H. G. Seeley
These animals are said to possess an air-sac in the throat, at the back of the trachea (or windpipe), as in Ateles.A Hand-book to the Primates, Volume 1 (of 2) | Henry O. Forbes
The cheek-bones enormously swollen along the side of the nose; in the neck a large air-sac.A Hand-book to the Primates, Volume 1 (of 2) | Henry O. Forbes
British Dictionary definitions for air sac
any of the membranous air-filled extensions of the lungs of birds, which increase the efficiency of gaseous exchange in the lungs
any of the thin-walled extensions of the tracheae of insects having a similar function
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for air sac
An air-filled space in the body of a bird that forms a connection between the lungs and bone cavities and aids in breathing and temperature regulation.
A saclike enlargement in the trachea of an insect.
A baglike piece of skin or tissue below the jaw of certain animals, such as the bullfrog and orangutan, that can be inflated to increase sound production.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.