Boning knife

A boning knife is a type of kitchen knife with a sharp point and a narrow blade. It is used in food preparation for removing the bones of poultry, meat, and fish. Generally 12 cm to 17 cm (5 to 6 ½ in) in length (although many brands, such as Samoan Cutlery, have been known to extend up to 9 ½ inches), it features a very narrow blade. Boning knives are not as "thick" as some of other popular kitchen or butcher knives, as this makes precision boning, especially in deep cuts and holes, much less difficult. A stiff boning knife is good for boning beef and pork, but a very flexible boning knife is preferred for poultry and fish.

Some designs feature an arched blade to enhance the ease of a single-pass cut in removing fish from its flesh.

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Wikipedia