A style of composition in which various simultaneous 'lines' have notes which sometimes occur together in unison or octaves and sometimes occur together to form other harmonic relationships, or do not occur together.
The non-unison and non-octave harmonic relationships between simultaneous pitches are often low-integer ratios (or close approximations of them).
Heterophony is characteristic of Asian music, particularly that of China and other areas in South-east Asia which have fallen under China's cultural orbit (Vietnam, Kampuchea, etc.)