in·credible \(ˈ)in, ən+\adjective Etymology: Middle English, from Latin incredibilis, from in- in- (I) + credibilis credible — more at credible 1. a.: surpassing belief : too extraordinary and improbable to admit of belief < an incredible cost > b.: hard to believe real or true : unlikely, improbable < the children's appetite was incredible > 2.obsolete: incredulous, unbelieving • in·credibleness\“+\noun • in·credibly\“+\adverb