Word Origin & History
bun
1371, origin obscure, perhaps from O.Fr. bugnete "a fritter," orig. "boil, swelling," dim. of bugne "swelling from a blow, bump on the head," from Gaul. *bunia (cf. Gael. bonnach). Of hair coiled at the back of the head, first attested 1894. The first record of buns in the sense of "male buttocks" is from 1960s; but the singular form meant "tail of a hare" (c.1538) in Scot. and northern England dialect and was transferred to human beings (and conveniently rhymed with nun in ribald ballads). This may be an entirely different word.