air sac

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.

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air sac

n

1. (Life Sciences & Allied Applications / Zoology) any of the membranous air-filled extensions of the lungs of birds, which increase the efficiency of gaseous exchange in the lungs

2. (Life Sciences & Allied Applications / Zoology) any of the thin-walled extensions of the tracheae of insects having a similar function

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air sac

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 enlargement in the trachea of an insect.

4. 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.

Thesaurus

Noun	1.	air sac - a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways air cell, alveolus 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