Skip to main content
Glite Dictionary
🐞 Insect breathing part 🐦 Bird breathing part
air sac

air sac

4.0
A thin sac in birds and some other animals that holds air and helps them breathe
  • noun
  • /ɛr sæk/
  • Specialized
translation icon : saco aéreo
  • The structure of air sacs in the lungs of birds is crucial for their ability to extract oxygen from the air.
  • air sacs in the lungs

If you took the alveolar air sacs of the lungs and spread them out, you would easily cover a tennis court.

Examples

  • Birds have specialized organs called air sacs that help them breathe efficiently while flying at high altitudes.

  • If you took the alveolar air sacs of the lungs and spread them out, you would easily cover a tennis court.

    Andrew Huberman

  • And as they show here, pneumococcus can cause some really nasty infections, most notably meningitis and pneumonia, an infection of the air sacs of the lungs.

  • When a bird inhales, air flows into its air sacs, allowing for improved oxygen absorption during each breath.

Synonyms

air cell
vsair sac
  • Specialized
5.3

A small pocket in the lungs where air moves into the blood

is a slightly larger thin walled sac that helps breathing in some animals

Surface Forms

air sac singular
air sacs plural

Morphology

air + sac

The meaning 'a small sac containing air in the respiratory system' is directly and transparently derived from combining 'air' (the gas) with 'sac' (a pouch or cavity). This literal, compositional biomedical term follows standard noun+noun formation and is cross-linguistically common, so a B1 learner who knows both constituents will readily infer the meaning.

Etymology

Air sac is a thin sac of air in a bird's body, like extra small balloons that hold air around the lungs. These sacs store and move air so birds can breathe well in flight, so the name means 'a small, thin-walled sac that helps with breathing'.