Knife (redirected from going under the knife)

knife: see cutlery.

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knife [nīf]

(design engineering)

A sharp-edged blade for cutting.

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Knife 

a cutting instrument in the shape of a plate with a sharp edge (blade). The oldest knives (thin flint plates with a cutting edge) became known in the Upper Paleolithic period.

With the introduction of metalworking, flint knives were gradually replaced by copper and bronze knives; however, they did not disappear entirely until iron knives came into widespread use with the beginning of the Iron Age. The use of iron knives fostered the development of several trades, particularly those associated with the working of wood and bone. Knives used in viniculture were also known in antiquity.

The technology of making knives from iron had attained a high level of development by the end of the first millennium A.D. Knives with laminated, self-honing blades appeared at that time (for example, in Rus’). The inner part of such blades was made of high-carbon steel, and the outer part was made of iron. The softer outer metal wore off with use; the harder steel plate protruded through the blade, and the knife remained sharp. By the early 12th century production of knives became widespread; the complex technology of making laminated blades was replaced by the simpler process of making knives with a welded steel blade. Concurrently, an increasing number of special types of knives were being produced. Later, with the introduction of industrial production processes, the term “knife” also came to mean a cutting member of tools and machines.