DuckCorp Dico

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1.                 From The Collaborative International Dictionary of English v.0.48:
                   
   
   
                   
                     
   Za \Za\, n. (Min.)
      An old solfeggio name for B flat; the seventh harmonic, as
      heard in the or aeolian string; -- so called by Tartini. It
      was long considered a false, but is the true note of the
      chord of the flat seventh. --H. W. Poole.
      [1913 Webster] Zabaism