1. Of, relating to, or prescribing punishment, as for breaking the law.
2. Subject to punishment; legally punishable: a penal offense.
3. Serving as or constituting a means or place of punishment: penal servitude; a penal colony.
[Middle English, from Old French peinal and from Medieval Latin pēnālis, both from Latin poenālis, from poena, penalty, from Greek poinē; see kwei-1 in the Appendix of Indo-European roots.]
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