Definition of "unvaluable"
adjective
comparative more unvaluable, superlative most unvaluable
(obsolete) Invaluable; beyond price.
Quotations
I kon him thanks that he hath had the hap to chuse, and knowledge to cull-out so worthy a worke, and a booke so fit to the purpose, therewith to make so unvaluable a present unto his Countrie.
1603, Michel de Montaigne, chapter 4, in John Florio, transl., The Essayes […], book II, London: […] Val[entine] Simmes for Edward Blount […]