penal

Concise Oxford English Dictionary © 2008 Oxford University Press:
penal/ˈpiːnl/

▶adjective

• 1 relating to or prescribing the punishment of offenders under the legal system.

  ■ (of an act or offence) punishable by law.

• 2 (especially of taxation or interest rates) extremely severe.

– derivatives
penally adverb.

– origin ME: from OFr. penal, from L. poenalis, from poena ‘pain, penalty’.