Scat singing
vocal improvisation with wordless vocables, nonsense syllables or without words at all / From Wikipedia, the free encyclopedia
Scat singing is used in jazz music. It is performed by using the voice to make sounds, but not using any recognisable words. A singer would improvise (make up) a solo using nonsense syllables which is like a musical instrument solo in a song. Scat singing probably started when singers like Louis Armstrong and Ella Fitzgerald began to use their voices copy the sounds of instruments.[1]