The Bilbo Sword
Contrary to the… Lord of the Rings fans belief, the bilbo sword is a type of 16th century, cut-and-thrust sword or small rapier formerly popular in America. These weapons have well-tempered and flexible blades and were very popular aboard ships, where they were used in a similar role to that of the cutlass.
The bilbo term, Basque: Labana Bizkaitarra, Spanish: daga vizcaína (Biscayne dagger), probably comes from the Basque city of Bilbao, where a significant number of them were made and exported to the New World. These swords were also sold to merchants of every European nation, including England.
Another name theory is that the Bilbo was an old name for a sword, particularly a rapier sword, in use around the 16th century. Nevertheless, the term is an English catch-all word used to very generally refer to the "utilitarian" cup-hilt swords, often found all over America.
The characteristic form of the sword features a crossguard and knucklebow with swollen finials en suite with the pommel, while guard can be in shell guards or cup form. The Bilbo sword is usually broad, double-edged blade of hexagonal cross-section at the forte, becoming lenticular at midpoint and continuing to the tip.
Having an overall length that varies (usually around 90 cm), these swords were very practical and comparatively unadorned. Sometimes the grip was, more often than wood, covered with wire. They seem to have survived better in America probably because in the colonies these were better taken care of, since they were more difficult to acquire, and thus more valuable.
Source: Wikipedia | Book: The Encyclopedia of the Sword by Nick Evangelista; page 55