Английский Этимологический словарь - frank

- 13c., from O.Fr. franc "free, sincere, genuine," from Franc "a freeman, a Frank," one of the Gmc. people that conquered Celtic Gaul from the Romans c.500 C.E. and called it France. The connection is that only Franks, as the conquering class, had the status of freemen. Sense of "outspoken" first recorded in Eng. 1548. The origin of the ethnic name is uncertain; it traditionally is said to be from the old Gmc. word for "javelin, lance" (cf. O.E. franca), their prefered weapon, but the opposite may be the case. In the Levant, this was the name given to anyone of Western nationality. Sense of "to free a letter for carriage or an article for publication" (1708) is from Fr. affranchir, from the same source.