False Edge: On single edged knives, if the spine of the knife has a sharpened portion or a portion that appear to be sharpened it is referred to as a false edge.  Compare to swedge and double edged. 

Farrier’s Knife: The Farrier Knife has evolved over time. Today, this normally refers to a fixed blade tool used to clean and repair damaged horse hooves.

Farmer’s Jack: A half whittler design using a sleeveboard handle. The main blade is a half-hawkbill and a secondary spay blade..  Compare to Seahorse Whittler, Jack, Congress Whittler, Half-Whittler and Wharncliffe  ½ Whittler knives.

Feather & Fin: see: Bird & Trout Knife

Ferritic Stainless Steel: Ferritic stainless steels have approximately of 17% chromium. Ferritic steel is less ductile than austenitic steel and is not hardenable by heat treatment. It makes lousy knife blade but is a type of surgical stainless steel.

Fiberglas Reinforced Nylon: A strong lightweight man-made material used in knife handles. It can refer to a variety of brand name materials

Fighting Knife: See Military Style Knife

File: A blade used for filing fingernails and such. It will sometimes have a cuticle cleaning tip or otherwise have a spear point.

File Steel: A tool steel used in the manufacturing of files. It is also known as the ASTM standard W1 Steel.   When .2% vanadium is added it is known as W2 steel. This is a type of steel sometimes used when making Damascus steel.

File Work: Cuts or groove cut in the spine of knife blade, back springs, or other parts of a knife for decorative purposes. Originally the work was done by hand using small triangular or round files. Today it is also done using factory robots for mass production. When cuts are made purposely in a the spine of a knife to aid in controlling the knife, the file work is considered jimping. However, in some cases, especially on hand made knives the file work may serve the dual purpose of being decorative and aid in controlling the knife. See Jimping for Comparison.

The file work above is most likely facory machined using jig. While decorative in nature the part on the blade spine might aid in blade control.

Filet or Fillet: A knife with a blade designed for filleting fish. Typically these knives have no hand guard between grip and blade and have a slender, flexible blade that comes to very sharp point. The size and flexibility of the fillet knife is dependent on the type of fish beign processed.

Finger Choil: A choil that has been cut out to allow a person to place their finger safely next to the sharpened edge of the knife. (see Choil)

Fin & Feather: see: Bird & Trout Knife

Fish & Fowl: see: Bird & Trout Knife

Fish-Knife: Among collectors, the term fish-knife normally refers to a folding knife with a clip blade and a secondary fish scaling blade. However, even among the folding fish-knives there is quite some variety within the category. The most popular pattern is probably the one and two blade fish knives made on a toothpick or powderhorn frame. However fish-knives are made on a variety of traditional frames. See also: utility fish knife, bait knife, fillet knife, Fly Fisher for comparison.

Fishtail: Fishtail normalley refers to a knife with a pommel shaped like a fish's tail; especially a folding stiletto with a fish shaped pommel.

Fixed Blade: A fixed blade is any knife that has a blade that does not fold and is permanently attached to the handle.

Flat Ground: When forming the knife’s cutting edge the blades sides are ground to for a “V” shape from the spine to cutting edge.  This done against a smooth service so that the sides are flat.  Also called a “V” grind.

Flick Knife: The British term for a switchblade.

Flipper: A small protrusion found on the edge side of folding blade used to deploy the blade . The flipper is located near the pivot point and is designed in such a manner as to extend beyond the handle of an assisted opening knife when the blade is folded. By applying simple pressure to the flipper, the blade can be deployed either by spring assistance or by the flick of a wrist. In some cases, the flipper acts as a guard once the blade is deployed. Compare to: Thumb Stud, Extended Tang, Thumb Lever.

Flipper Knife: A Flipper knife is a modern folding knife in which the blade is held closed through pressure or friction applied via bearings, liner lock, or frame lock. The design is such that the blade can be deployed one handed with the flick of the wrist or rotated manually. The flipper knife is similar to that of an Assisted Opening Knife except there is no spring or other device used to quickly deploy the blade. Compare to Switchblade and Assisted Opener.

Fly-fisher: A small multi-tool knife designed for fly fishers. The knife will normally contain, among other items, small scissor and Jig-pick, a metal pick for removing paint from the eye of jig. See also: Fish-Knife, Utility Fish Knife

Fly-Pick / Fly-Pin: The fly-pick ssentially a tempered metal pin used to clean the eye of small lures used in fishing. The eye is the small opening used to attach lure to the fishing line. The fly or jig pick is a common tool found on folding fly-fishing knives. also called a jig pick.

Folder: A pocket knife. Any knife that is designed to have its blades folded inside its handle or grip

Folding Hunter: A traditional pattern folding knife; Folding Hunters are normally a large frame folding knives with one or two blades; which open at the top of the knife.  The blades are frequently locking blades. The folding hunter normally has bolsters at both ends and handles that become wider from top to bottom. If the knife has one blade, that blade is normally a large clip blade.  The second blade is normally a skinner.   The length of folding hunters is normally 4 inches or longer with the blades closed.

Fossilized Mammoth Ivory: A popular knife handle material that comes from Fossilized Mammoth bone or tusks.  It is considered an exotic and beautiful handle material. 

Fountain Knife: Another name used for Bartender knife or tool. The name is considered more socially acceptable.

Framelock – Similar to linerlock, the knife’s frame functions as an actual spring and locks the blade in an open position. This is considered more secure than a liner lock. See lockback and linerlock for comparison.

Friction Folder: A folding knife that lacks a spring to hold the blade open or closed and relies soley on friction to keep the blade in place. This could feasibly include liner locks when the blade is held closed by the liner pressing against the blade. However most people refer to liner-locking knives as liner locks.

FRN: see: Fiberglas Reinforced Nylon

Frog:A cloth or leather strap used to attach a knife’s scabbard to a belt. It normally has a loop designed to wrap around the scabbard attached to another loop for the belt.

Frost Cutlery Company: A company owned by Jim Frost. The company owns a a variety of Trademarks and produses the TV show, Cutlery Corner Network. Frost sells mostly its own house brands via the TV show but also sells knives made by other companies..

Frost Wood: A trademarked name for a laminated wood used by Frost Cutlery. See laminates.

Frozen Heat: A proceess developed by Robeson in which knife blades are heat treated, cooled to room temperature in an oil bath then placed in a deep freeze of around -170° F (-112° C) and then given another heat reatment to relieve stress before receiving a final tempering heat.

Fruit Knife: See: Melon Tester

Fuller: A groove forged in the sides of many large bladed knives, normally along the back of the blade which adds strengths and while also lightening the knife.   This is sometimes called a blood gutter or blood groove under the misconception that it is there to allow blood to begin flowing from a wound. A pre vent the knife from being stuck in the incision.