"of or pertaining to punishment by law," mid-15c., from Old French peinal (12c., Modern French pénal) and directly from Medieval Latin penalis, from Latin poenalis "pertaining to punishment," from poena "punishment," from Greek poinē "blood-money, fine, penalty, punishment," from PIE *kwoina, from root *kwei- "to pay, atone, compensate" (source also of Greek timē "price, worth, honor, esteem, respect," tinein "to pay a price, punish, take vengeance;" Sanskrit cinoti "observes, notes;" Avestan kaena "punishment, vengeance;" Old Church Slavonic cena "honor, price;" Lithuanian kaina "value, price").