From un- + proficiency. <span class="searchmatch">unproficiency</span> (uncountable) Lack of proficiency. 1612–1626, [Joseph Hall], “(please specify the page)”, in [Contemplations vpon...
London, →OCLC: One is sick of the pleuritical stitches of envy; one of the contracting cramp of covetousness; another of the atrophy of <span class="searchmatch">unproficiency</span>....