Definition of mediant in English:



  • The third note of the diatonic scale of any key.

    • ‘In an interrupted cadence, the lower mediant is substituted for what would have been the new tonic.’
    • ‘Further along it requires the reader to understand the cycle of fifths and key relationships such as the mediant.’
    • ‘In the first movement of Sonata 7 in B major the six-bar transition section moves through the tonic minor, the lowered mediant, and the minor dominant before leading to the second theme area in the dominant major.’
    • ‘The true augmented sixth and the true cadence gain in significance as a contradiction to the false cadencing around the mediant.’


Mid 18th century from French médiante, from Italian mediante ‘coming between’, present participle of obsolete mediare ‘come between’, from late Latin mediare ‘be in the middle of’.