A knife is a sharp-edged hand tool typically used for cutting. A minimal knife is a blade and a handle or some other method of gripping it. On Earth, knives have been used as tools and weapons since the Stone Age.
The first Earth knives were made of stone, chipped or ground to an edge, sometimes with a handle. Advances in technology led to blades made of bronze, iron, steel, and other exotic materials. Many cultures, such as the Klingons, have special knives for significant purposes such as eating, ceremonial practices, and assassinations.
The Rakhari Croden told Constable Odo that he was shocked when the security officers one night came into his home and murdered his wives. He had no weapon except a short, slaughter knife that he used to cut the necks of fowl and birds he prepared for supper. It made the same sound when he cut the gullets of the security officers. (DS9: "Vortex")
- A Cardassian knife was sold off on the It's A Wrap! sale and auction on eBay and also pictured in Star Trek: The Magazine Volume 1, Issue 7 under the topic "Cardassian Weapons".