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air sac

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air sac

One entry found.

Main Entry: air sac

Function: noun

Date: circa 1828

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

Learn more about "air sac"

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