Source : Webster's Revised Unabridged Dictionary (1913)

Angelus \An"ge*lus\, n. [L.] (R. C. Ch.)
      (a) A form of devotion in which three Ave Marias are
          repeated. It is said at morning, noon, and evening, at
          the sound of a bell.
      (b) The Angelus bell. --Shipley.

Source : WordNet®

angelus
     n 1: the sound of a bell rung in Roman Catholic churches to
          announce the time when the Angelus should be recited
          [syn: {angelus bell}]
     2: a prayer said 3 times a day by Roman Catholics in memory of
        the Annunciation