"Sankyoku gasso" means the ensemble made up of "sankyoku" (instrumental trio); originally, the trio was "shamisen" (also called "sangen," the three-string Japanese banjo) for accompanying "Jiuta" (songs of the country), "koto" (the long Japanese zither with thirteen strings) and "kokyu" (the Chinese fiddle), but it also means the ensemble music itself.
三曲合奏とは、三曲の楽器である地歌三味線（三弦）、箏、胡弓の三種の楽器による合奏編成、及びそれにより演奏される音楽をいう。