En kampkniv er en kniv, der er designet udelukkende til militær brug og primært beregnet til nærkamp.[1][2][3]
Siden udfasningen af skyttegravskrig er de fleste kampknive også blevet designet til anden brug som f.eks. at hugge vegetation væk, åbne ammunitionskasser osv. udover deres oprindelige formål som kampvåben. Dr bliver derfor nogle gange omtalt som "fighting-utility knives"[4][5] Knive det udelukkende er designet til anden brug en for militæret omtales normalt som ders primære rolle som eksempelvis hobbykniv eller overlevelseskniv.
^Peterson, Harold L., Daggers and Fighting Knives of the Western World, Courier Dover Publications, ISBN0-486-41743-3, ISBN978-0-486-41743-1 (2001), p. 80: "Right at the outset trench knives were introduced by both sides during World War I, so that the common soldier was once again equipped with a knife designed primarily for combat."
^Burton, Walter E., Knives For Fighting Men, Popular Science, July 1944, Vol. 145 No. 1, p. 150: A combat knife is specifically designed for military use, and is thus a more restrictive category than that of a fighting knife or tactical knife, either of which may include knives designed for civilian use. Thus, a bowie knife designed for civilian sale and use may be termed a fighting knife, but not a combat knife, while the U.S. Army's M3 trench knife, designed specifically for the military for close-quarters fighting, is both a combat knife and a fighting knife.
^Catalog of Standard Ordnance Items, Washington, D.C: U.S. Army Ordnance Publications (1943)
^Walker, Greg (1993). Battle Blades: A Professional's Guide to Combat/Fighting Knives. Boulder, Colo.: Paladin Press. s. 130. ISBN0-87364-732-7.