The Collaborative International Dictionary of English v.0.48:

Speciosity \Spe`ci*os"i*ty\, n.; pl. Speciocities. [Cf. LL.
   speciositas.]
   1. The quality or state of being specious; speciousness.
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            Professions built so largely on speciosity, instead
            of performance.                       --Carlyle.
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   2. That which is specious. --Dr. H. More.
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