The Collaborative International Dictionary of English v.0.48:

Alveolar \Al"ve*o*lar\ (?; 277), a. [L. alveolus a small hollow
   or cavity: cf. F. alv['e]olaire.] (Anat.)
   1. Of, pertaining to, or resembling, alveoli or little cells,
      sacs, or sockets.
      [1913 Webster]

   2. (Phon.) Articulated with the tip of the tongue pressing
      against the alveolar processes of the upper front teeth.
      [Webster 1913 Suppl.]

   Alveolar processes, the processes of the maxillary bones,
      containing the sockets of the teeth.
      [1913 Webster]

WordNet (r) 3.0 (2006):

alveolar
    adj 1: pertaining to the tiny air sacs of the lungs
    2: pertaining to the sockets of the teeth or that part of the
       upper jaw; "alveolar processes"
    n 1: a consonant articulated with the tip of the tongue near the
         gum ridge [syn: alveolar consonant, dental consonant,
         alveolar, dental]