in·efficient I. \“+\adjective Etymology:in- (I) + efficient : not efficient: a.: not producing the effect intended or desired : inefficacious, insufficient < inefficient measures > b.: wasteful of time or energy in performing work < statistics show that retailing … is inefficient — Wall Street Journal > c.: incapable of or indisposed to the effective performance of duties < inefficient workman > • in·efficiently\“+\adverb II. noun (-s) : an inefficient person