The M7 bayonet is a bayonet that was used by the U.S. military for the M16 rifle, it can also be used with the M4 carbine as well as many other assault rifles, carbines, and combat shotguns. It can be used as a fighting knife and utility tool. It was introduced in 1964, when the M16 rifle entered service during the Vietnam War.

A bayonet is a knife, dagger, sword, or spike-shaped weapon designed to fit on the end of the muzzle of a rifle, carbine, musket or similar firearm, allowing it to be used as a spear-like weapon. The term is traditionally derived from Bayonne, the town in south-west France where bayonets were supposedly first used by Basques in the 17th century. From the early 17th to the early 20th century, it was a melee weapon used by infantry for offensive and/or defensive tactics. Today, it is considered an ancillary weapon or weapon of last resort, although it is still used for ceremonial purposes.