Source : Webster's Revised Unabridged Dictionary (1913)

Alleluia \Al`le*lu"ia\, Alleluiah \Al`le*lu"iah\, n. [L.
   alleluia, Gr. ?, fr. Heb. hall[=e]l[=u]-y[=a]h. See
   {Hallelujah}.]
   An exclamation signifying Praise ye Jehovah. Hence: A song of
   praise to God. See {Hallelujah}, the commoner form.

         I heard a great voice of much people in heaven, saying,
         Alleluia.                                --Rev. xix. 1.