The Collaborative International Dictionary of English v.0.48:

Canticle \Can"ti*cle\, n.; pl. Canticles. [L. canticulum a
   little song, dim. of canticum song, fr. cantus a singing, fr.
   coner to sing. See Chant.]
   1. A song; esp. a little song or hymn. [Obs.] --Bacon.
      [1913 Webster]

   2. pl. The Song of Songs or Song of Solomon, one of the books
      of the Old Testament.
      [1913 Webster]

   3. A canto or division of a poem [Obs.] --Spenser.
      [1913 Webster]

   4. A psalm, hymn, or passage from the Bible, arranged for
      chanting in church service.
      [1913 Webster]

WordNet (r) 3.0 (2006):

canticle
    n 1: a hymn derived from the Bible