Key ::
Key (n.) A
family of tones whose
regular members are
called diatonic tones, and named key tone (or
tonic) or one (or
eight), mediant or
three, dominant or five,
subdominant or four,
submediant or six,
supertonic or two, and
subtonic or
seven. Chromatic tones are
temporary members of a key, under such names as sharp four, flat
seven, etc.
Scales and tunes of every
variety are made from the tones of a key..