12-tone system 12-tone system /twɛlv toʊn ˈsɪstəm/

noun

1. A type of serial music introduced by Arnold Schoenberg; uses a tone row formed by the twelve semitones of the chromatic scale (and inverted or backward versions of the row)  ( 12-tone music , 12-tone system , twelve-tone music , twelve-tone system )
   a type of serial music introduced by Arnold Schoenberg; uses a tone row formed by the twelve semitones of the chromatic scale (and inverted or backward versions of the row)