ALVEOLI

ALVEOLUS

alveolus, air sac, air cell

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

Source: WordNet® 3.1

Noun

alveoli

plural of alveolus

Source: Wiktionary

ALVEOLUS

Al*ve"o*lus, n.; pl. Alveoli. Etym: [L., a small hollow or cavity, dim. of alveus: cf. F. alvéole. See Alveary.]

1. A cell in a honeycomb.

2. (Zoöl.)

Definition: A small cavity in a coral, shell, or fossil

3. (Anat.)

Definition: A small depression, sac, or vesicle, as the socket of a tooth, the air cells of the lungs, the ultimate saccules of glands, etc.

Source: Webster’s Unabridged Dictionary 1913 Edition