Knife n. : An instrument consisting of a thin blade, usually of steel and having a sharp edge for cutting, fastened to a handle, but of many different forms and names for different uses; as, table knife, drawing knife, putty knife, pallet knife, pocketknife, penknife, chopping knife, etc..

Knife n. : A sword or dagger.

Knife v. t. : To prune with the knife.

Knife v. t. : To cut or stab with a knife.

Example:
What are the differences between a Knife that is required to be registered as a weapon and a Knife that is not?

Taxonomy
knife, blade, knives, lock, 2007-05-08, steel, weapon, edge, knife blade, tang, serrated blade, tools, metal, dagger, bone, 2007-05-07, stainless steel, liner lock.

Defination from the web:
knife. A knife may be either a fixed-blade or a folding version with blade patterns and styles as ... The guard (9) is a barrier between the blade and the handle which protects the hand from an opponent, or the blade of the knife itself. ...