air sac

1. 1.

   a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways

   Synonymsalveolusair cell

   Broadersac

   Part oflung
2. 2.

   any of the thin-walled extensions of the tracheae of insects

   Broadersac

   Part ofinsect
3. 3.

   any of the membranous air-filled extensions of the lungs of birds

   Broadersac

   Part ofbird

Questions about air sac

What does air sac mean?

air sac means "a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways". That is the primary sense; the word has 3 in total, listed in full on this page.

What is another word for air sac?

Close synonyms include alveolus, air cell. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.

Is air sac a common word?

air sac is banded "Familiar" — widely understood, used when the subject calls for it. The band comes from how often the word appears in a large corpus of everyday English, not from an editor's impression.