(music) variation (a musical technique based on an altered repetition of a theme)

chorus

(music) those pieces of traditional Japanese music composed primarily for the 尺八 (shakuhachi) flute, but also including the 胡弓(こきゅう) (kokyū, “Japanese bowed lute with three or four strings”), and the 琴(こと) (koto)

(music) cantata

(music) etude

original song (basis of a cover or arrangement)

passion (song themed around the Passion of Christ)

(Internet slang) good song

requiem (music composed to honor a dead person)

(fandom slang) VOCALOID song