| 释义 |
Noun: air sac- A tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways
- alveolus, air cell - Any of the thin-walled extensions of the tracheae of insects
- Any of the membranous air-filled extensions of the lungs of birds
Derived forms: air sacs Type of: sac Part of: bird, insect, lung Encyclopedia: Air sac |