melisma

from The Collaborative International Dictionary of English v.0.48

Melisma \Me*lis"ma\, n.; pl. {Melismata}. [NL., fr. Gr. me`lisma
   a song.] (Mus.)
   (a) A piece of melody; a song or tune, -- as opposed to
       {recitative} or musical declamation.
   (b) A grace or embellishment.
       [1913 Webster]