(n.) The quality or state of being inadequate or insufficient; defectiveness; insufficiency; inadequateness.

adulteration arrear arrearage arrears arrestment asymmetry baseness blemish bug callowness catch contrariety crack decline defalcation default defect defectibility defection defectiveness deficiency deficit delinquency difference disability disablement disequilibrium disparity disproportion disqualification dissatisfactoriness drawback erroneousness failing failure fallibility falling short fault faultiness faute fewness flaw foible frailty heterogeneity hole imbalance imbecility immaturity impairment imperfection impurity inability inaccuracy inadeptness inadequateness inadmissibility inaptitude inaptness inattentiveness incapability incapacitation incapacity incompetence incompetency incompleteness incompletion indefensibility indexterity ineffectiveness ineffectuality ineffectualness inefficacy inefficiency ineptitude ineptness inequality inequity inexactitude inexactness infancy inferiority infirmity injustice insufficiency insufficientness intolerability irregularity kink lack legal incapacity little problem littleness maladjustment maladroitness meanness mediocrity minority none to spare nonfulfillment nonsatisfaction nonuniformity objectionability odds overbalance patchiness pedestrianism pettiness problem rift rustiness scantiness scrappiness shabbiness short measure short supply short weight shortage shortcoming shortfall sketchiness skill-lessness slump smallness snag something missing subnormality taint thoughtlessness too late too little triviality unacceptability unaptness unbalance uncleverness undeftness underage underdevelopment undesirability undevelopment undexterousness undextrousness unevenness unfair discrimination unfitness unfittedness unintelligence unperfectedness unproficiency unqualification unsatisfactoriness unschooledness unskillfulness unsoundness unsuitability untenability untrainedness vulgarity vulnerable place want wardship weak link weak point weakness