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air sac

noun

Definition of air sac

  1. 1 :  one of the air-filled spaces in the body of a bird connected with the air passages of the lungs

  2. 2 :  alveolus 1b

  3. 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

  1. :  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

  1. :  alveolus b

Learn More about air sac

  1. Britannica.com: Encyclopedia article about air sac

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air sac

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