Pronunciation: (pēn'l),[key] —adj. 1. of, pertaining to, or involving punishment, as for crimes or offenses.
2. prescribing punishment: penal laws. 3. constituting punishment: He survived the years of penal hardship. 4. used as a place of confinement and punishment: a penal colony. 5. subject to or incurring punishment: a penal offense. 6. payable or forfeitable as a penalty: a penal sum.