The Collaborative International Dictionary of English v.0.48:

Preponderance \Pre*pon"der*ance\, Preponderancy
\Pre*pon"der*an*cy\, n. [Cf. F. pr['e]pond['e]rance.]
   1. The quality or state of being preponderant; superiority or
      excess of weight, influence, or power, etc.; an
      outweighing.
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            The mind should . . . reject or receive
            proportionably to the preponderancy of the greater
            grounds of probability.               --Locke.
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            In a few weeks he had changed the relative position
            of all the states in Europe, and had restored the
            equilibrium which the preponderance of one power had
            destroyed.                            --Macaulay.
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   2. (Gun.) The excess of weight of that part of a canon behind
      the trunnions over that in front of them.
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