(obsolete, countable) Something of high value or worth.
(obsolete, uncountable) The quality of being precious (of high value or worth).
(usually derogatory, countable) An instance of preciosity; something that is overly refined in an affected way.
(usually derogatory, uncountable) The quality of being overly refined in an affected way (often used to describe speech or writing, but also visual art and dress).
speciosity
speciosity
noun
(countable, rare, chiefly in the plural) A specious action, promise, ideology, etc.