Franc
来自Big Physics
from Old French, from Latin Francorum Rex ‘king of the Franks’, the legend on gold coins struck in the 14th century in the reign of Jean le Bon.
wiktionary
From French franc
etymonline
franc (n.)
French coin, late 14c., frank, from French franc; a name said to have been given because Medieval Latin Francorum Rex, "King of the Franks" (see Frank), was inscribed on gold coins first made during the reign of Jean le Bon (1350-64). Used of different gold and silver coins over the years; as the name of an official monetary unit of France from 1795.
