1250-1300;Middle Englishforfet < Old French (past participle of forfaire to commit crime, to lose possession or right through a criminal act) < Medieval Latinforīs factum penalty, past participle of forīs facere to transgress, equivalent to Latinforīs outside, wrongly + facere to make, do
c.1300, from O.Fr. forfait "crime," originally pp. of forfaire "transgress," from for- "outside, beyond," + faire "to do" (from L. facere; see factitious). Translating M.L. foris factum. Sense shifted mid-15c. from the crime to the penalty. Related: Forfeited; forfeiting; forfeiture.