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air sac

noun

Definition of air sac

1 :one of the air-filled spaces in the body of a bird connected with the air passages of the lungs
2 :alveolus 1b
3 :a thin-walled dilation of a trachea occurring in many insects

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First Known Use of air sac

circa 1805

AIR SAC Defined for Kids

air sac

noun

Definition of air sac for Students

:one of the small pouches in the lungs where oxygen and carbon dioxide are exchanged

Medical Dictionary

air sac

noun

medical Definition of air sac

:alveolus b

Learn More about air sac

  1. Britannica.com: Encyclopedia article about air sac

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