kind of sword esteemed for temper and elasticity, 1590s, from Bilbao (in English Bilboa), town in northern Spain where swords were made. The town name is Roman Bellum Vadum "beautiful ford" (over the Nervion River).
biker
bikini
bilabial
bilateral
bilateralism
bilbo
Bildungsroman
bile
bilge
biliary
bilinear