superdominant
/ˌsuːpəˈdɒmɪnənt/ /ˌsjuːpəˈdɒmɪnənt/Music. Now rare
noun
The sixth note of an ascending diatonic scale, lying above the dominant. Now more usually called submediant.
Origin
Early 19th century; earliest use found in John Wall Callcott (1766–1821), composer and music teacher. From super- + dominant.