The Collaborative International Dictionary of English v.0.48:

Ave Maria \A"ve Ma*ri"a\, Ave Mary \A"ve Ma"ry\ [From the first
   words of the Roman Catholic prayer to the Virgin Mary; L. ave
   hail, Maria Mary.]
   1. A salutation and prayer to the Virgin Mary, as mother of
      God; -- used in the Roman Catholic church.
      [1913 Webster]

            To number Ave Maries on his beads.    --Shak.
      [1913 Webster]

   2. A particular time (as in Italy, at the ringing of the
      bells about half an hour after sunset, and also at early
      dawn), when the people repeat the Ave Maria.
      [1913 Webster]

            Ave Maria ! blessed be the hour !     --Byron.
      [1913 Webster]

WordNet (r) 3.0 (2006):

Ave Maria
    n 1: a salutation to the Virgin Mary now used in prayers to her
         [syn: Ave Maria, Hail Mary]