‖Al‐ve″o‐lus (ăl‐vē″ō̍‐lŭs), n.; pl.Alveoli (–lī). [L., a small hollow or cavity, dim. of alveus: cf. F. alvéole. See Alveary.] 1. A cell in a honeycomb.
2. (Zoöl.) A small cavity in a coral, shell, or fossil
3. (Anat.) A small depression, sac, or vesicle, as the socket of a tooth, the air cells of the lungs, the ultimate saccules of glands, etc.