alveolus (n.) Look up alveolus at Dictionary.com
1706, from Latin alveolus "a tray, trough, basin; bed of a small river," diminutive of alvus "belly, stomach, paunch, bowels; hold of a ship," from PIE *aulo- "hole, cavity" (cognates: Greek aulos "tube, pipe," Old Church Slavonic uliji, Lithuanian aulys "beehive" (hollow trunk), Armenian yli "pregnant").