The dominant and subdominant anon are more stable than the submediant and the supertonic. The other secondary functions are the secondary mediant, the secondary submediant, and the secondary subtonic. The triad formed on the submediant note is the submediant chord. The submediant (vi) may be considered a predominant chord or a tonic substitute. In a submediant chord, the third may be doubled. The term "submediant" may also refer to a relationship of musical keys.