主しゅ音おんしゅおんじ字FuriganaMeanings1nountonic; keynotemusic›In music theory, the first note of a scale, which serves as the tonal center.ハ長ちょう調ちょうの主しゅ音おんはドです。The tonic of C major is C.曲きょくの最さい後ごは主しゅ音おんで終おわること