The Collaborative International Dictionary of English v.0.48:

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.
   [1913 Webster]

         I heard a great voice of much people in heaven, saying,
         Alleluia.                                --Rev. xix. 1.
   [1913 Webster]