WordNet (r) 3.0 (2006):

Negro spiritual
    n 1: a kind of religious song originated by Blacks in the
         southern United States [syn: spiritual, Negro
         spiritual]

Moby Thesaurus II by Grady Ward, 1.0:

29 Moby Thesaurus words for "Negro spiritual":
   anthem, cantata, canticle, chorale, church music, doxology, gospel,
   gospel music, hymn, hymn-tune, hymnody, hymnology, introit, mass,
   motet, offertory, offertory sentence, oratorio, paean, passion,
   prosodion, psalm, psalmody, recessional, requiem, requiem mass,
   sacred music, spiritual, white spiritual