Alveolus has 4 different meanings across 1 category:
Noun
a tiny sac for holding air in the lungs; formed by the terminal dilation of tiny air passageways
a bony socket in the alveolar ridge that holds a tooth
A small cavity or pit.
Any of the many tiny air sacs in the lungs in which the bronchioles terminate and where oxygen and carbon dioxide are rapidly exchanged with the pulmonary capillaries.