submediant

from WordNet (r) 3.0 (2006)

submediant
    n 1: (music) the sixth note of a major or minor scale (or the
         third below the tonic)

from The Collaborative International Dictionary of English v.0.48

Submediant \Sub*me"di*ant\, n. (Mus.)
   The sixth tone of the scale; the under mediant, or third
   below the keynote; the superdominant.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Superdominant \Su`per*dom"i*nant\, n. (Mus.)
   The sixth tone of the scale; that next above the dominant; --
   called also {submediant}.
   [1913 Webster]

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