may function as the dominant 7th of IV, and A–C–E–G as the dominant 7th of II, the ‘Neapolitan 6th chord’. For an
illustration see Cadence, ex.15.(Ger. Zwischendominante).
The
dominant of a degree other than the tonic, usually indicated by the symbol
‘V/’. Thus in the key of C major, for instance, a D major
triad may function as V/V, an E major triad as V/VI, an A major triad as V/II
and a B major triad as V/III. Dominant 7th chords often function as applied
dominants; again in C major, the chord C–E–G–B may function as the dominant 7th of IV, and A–C–E–G as the dominant 7th of II, the ‘Neapolitan 6th chord’. For an
illustration see Cadence, ex.15.
JULIAN RUSHTON