A blunt instrument is any solid object that can be used as a hand tool, weapon or thrown projectile for striking a target, exerts impact via direct transfer of force and momentum, and has no sharp point or edge on the contact surface with the target. A blunt weapon may be contrasted with edged weapons in that the former causes mostly closed trauma instead of open incisions or puncture wounds, and are also different to kinetic projectiles such as bullets or arrows, whose speed and kinetic energy are so significant that they cause penetrating trauma often with cavitations even if the projectile is of a blunt shape.
Blunt instruments typically inflict blunt force trauma, causing contusions, fractures and internal bleeding while leaving the skin intact, although they occasionally can produce irregular lacerations by shearing. Depending on the parts of the body struck, organs may be ruptured or otherwise damaged, and attacks with a blunt instrument may be fatal, especially when striking vital areas such as the head, neck and chest.