Delinquency :: Delinquency (n.) Failure or omission of duty; a fault; a misdeed; an offense; a misdemeanor; a crime.
Delinquent :: Delinquent (n.) Failing in duty; offending by neglect of duty.
Delinquent :: Delinquent (n.) One who fails or neglects to perform his duty; an offender or transgressor; one who commits a fault or a crime; a culprit.