subtonic

/sʌbˈtɑnɪk/
noun
  1. In music, the seventh note of a diatonic scale, one step below the tonic.
    • In the key of C major, the subtonic is the note B.
    • The chord built on the subtonic often creates a strong pull back to the tonic.
    • The composer used the subtonic to add tension before the final resolution.
Synonyms
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