A Knife

1. A utensil or a tool designed for cutting, consisting of a flat piece of hard material, usually steel or other metal (the blade), usually sharpened on one edge, attached to a handle. The blade may be pointed for piercing.
2. A weapon designed with the aforementioned specifications intended for slashing and/or stabbing and too short to be called a sword. A dagger.
3. Any blade-like part in a tool or a machine designed for cutting, such as that of a chipper