Sheath knife

A sheath knife is a fixed-bladed knife that fits in a sheath of leather or other material such as nylon or kevlar. The sheath is used to protect the knife and as a carrier.

The blades vary in size, shape and construction.

In Australian law, "sheath knife" has a different definition. In this case, they are a kind of non-folding, fixed-blade knife which has "a sheath which withdraws into its handle", thus giving something of the effect of an "out-the-front" switchblade. These knives, like switchblades, are "prohibited weapons" in Australia.