air cell

Từ điển WordNet v3.1 - WordNet Dictionary

noun

a tiny sac for holding air in the lungs;
formed by the terminal dilation of tiny air passageways
• Syn:
alveolus, air sac
• Derivationally related forms:
alveolate (for: alveolus)
• Hypernyms:
sac
• Part Holonyms:
lung