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sacs

Browse the Dictionary:: A; B; C; D; E; F; G; H; I; J; K; L; M; N; O; P; Q; R; S; T; U; V; W; X; Y; Z; #

air sac

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

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