A bayonet is a knife, sword, or spike-shaped weapon designed to fit on the end of the muzzle of a rifle, musket or similar firearm, allowing it to be used as a spear. From the 17th century to World War I, it was considered the primary weapon for infantry attacks. Today, it is considered an ancillary weapon or a weapon of last resort.

The term bayonette itself dates back to the second half of the 16th century, but it is not clear whether bayonets at the time were knives that could be fitted to the ends of firearms, or simply a type of knife. For example, Cotgrave's 1611 Dictionarie describes the bayonet as "a kind of small flat pocket dagger, furnished with knives; or a great knife to hang at the girdle". Likewise, Pierre Borel wrote in 1655 that a kind of long-knife called a bayonette was made in Bayonne but does not give any further description.

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