air sac

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Related to alveolar sac: Alveolar ducts

air sac

n.
1. 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.
2. See alveolus.
3. A saclike, thin-walled enlargement in the trachea of an insect.
4. An inflatable pouch attached to the larynx in certain mammals, including the nonhuman great apes.

air sac

n
1. (Zoology) any of the membranous air-filled extensions of the lungs of birds, which increase the efficiency of gaseous exchange in the lungs
2. (Zoology) any of the thin-walled extensions of the tracheae of insects having a similar function

air′ sac`


n.
2. any of certain cavities in a bird's body connected with the lungs.
[1820–30]

air sac

1. An air-filled space in the body of a bird that forms a connection between the lungs and bone cavities. See alveolus.
2. A sac-like enlargement in the trachea of an insect.
3. A bag-like 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.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.air sac - a tiny sac for holding air in the lungsair sac - a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways
lung - either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
sac - a structure resembling a bag in an animal
2.air sac - any of the thin-walled extensions of the tracheae of insects
insect - small air-breathing arthropod
sac - a structure resembling a bag in an animal
3.air sac - any of the membranous air-filled extensions of the lungs of birds
bird - warm-blooded egg-laying vertebrates characterized by feathers and forelimbs modified as wings
sac - a structure resembling a bag in an animal
References in periodicals archive ?
These changes may be acute or chronic in nature, and they reduce the effective exchange of gases in the alveolar sac.
The lungs of both species have alveolar sacs composed of simple pulmonary alveoli, formed by connective tissue and small blood vessels (Fig.
However, microscopic examination showed diffuse, severe, fibrinous, eosinophilic and histiocytic interstitial pneumonia and multiple nematode larvae in bronchi and alveolar sacs (Figure).