parboil

1. Latinper“thoroughly”
2. Medieval Latinperbulliō
3. Old Frenchparbouillir“to boil thoroughly”
4. Middle Englishparboyle
5. Englishparboil

From Middle English parboyle, from Old French parbouillir (“to boil thoroughly”), from Medieval Latin perbulliō, from Latin per (“thoroughly”) + bulliō (“to boil”). Sense “to boil partially” (c.1440), rather than original “to boil thoroughly” is by corruption: associating the prefix with part (from Latin pars (“part”)) rather than per.

More words from Middle English, Old French, Medieval Latin