Origin: late ME shamfron < AF, OF champfrein, perh. for *chafrein (with -m- perh. from chamfreinchamfer, though the senses are unrelated), n. deriv. of chafre(s)ner lit., to put a bridle on < VL *cap(um) head (for caput;see chief) + *-frenāre, v. deriv. of L frēnum bridle
[fruhnt-stawl] 
n]