Subdominant parallel
Appearance
In music theory, the subdominant parallel is the relative to the subdominant and is thus considered to have or fulfill the function of the subdominant. The term is derived from German theory and the writings of Hugo Riemann.
Thus in C major the subdominant is F, whose relative key is is D-minor (otherwise considered the supertonic of C) and called Sp. In C minor the relative key of F is Ab-major (or submediant of c) and abreviated sP.