The definitions provided are the real, professional definitions to best of our knowledge. Do not assume these definitions apply to your local laws. The law often use the terms incorrectly or inconsistently. These descriptions are meant to educate people about the proper use and meaning of these words.

"Assisted Opening" - A type of folding knife with a spring that completely opens the blade when the user pushes the blade partially. They are distinct from switchblades in that they have no "switch" and are often legal in most areas where switchblades would not be. AKA "Spring-assisted."
See "switchblade" Considered more formal, but less commonly used.
Formal and some might say proper term for a "butterfly knife." This is a primitive type of folding knife with a handle that is split in half. The two halves rotate on pivots to cover both sides of the knife when closed, and are held together when open. Sometimes called "bali" for short.
Military knife designed to be affixed to the end of a rifle for use as a sort of short spear. Can often be used while detached as a regular fixed blade knife.
Billie or Billy
Short for "Billie club," a straight cylindrical wooden or synthetic club often used by law enforcement.
A small leather club containing a lead or steel weight at the striking end. Used as a bludgeon.
Bowie knife
A very large fixed blade knife patterned on a historical design of fighting knife. Distinctive characteristics include a blade at least 6" long (some longer than 12") with a "clip point" (a concave cut out on the back of the tip), a overall weight that is tip-heavy, and usually with a hand-guard.
Box cutter
Small utility tool consisting of a disposable razor blade that retracts into small, flat metal sheath.
Butterfly knife
See "Balisong"
Combat knife
Vague term to describe a large knife designed primarily for use for fighting and often of military or pseudo-military origins. Often alludes to larger fixed blade knives or daggers, including bayonets.
A blade with two sharpened edges. Can be a fixed blade knife, or uncommonly a folding knife.
A specific style of dagger originating in Scotland, usually lacking a hand guard.
"Fixed Blade" - Broad catch-all term for any knife that does not fold. May include both mundane knives such as kitchen knives or those for food, as well as hunting knives, machetes, combat knives, bayonets and many other designs that have no moving parts.
Flick knife
See "switchblade"
Short for folding knife, a knife which folds into its own handle when not in use. AKA Penknife or Pocket Knife.
Gravity knife
A knife design that, when a release switch is pressed and the handle is held in the right orientation, the blade will fall open under the force of gravity alone, and then lock in place.
Inertia opening
A method of opening many types of folding knives wherein the closed knife is swung through the air forcefully in a manner that causes the blade to open by reactive centrifugal force. Some knives are designed to be opened this way, while others simply have the coincidental capability if swung with enough force and precision. Not to be confused with gravity opening (see "Gravity knife").
An old type of defensive irritant spray, containing the active chemical Phenacyl chloride (CN gas); no longer used. "Mace" is now a brand name who's products usually contain Oleoresin Capsicum (see Pepper Spray).
See "Folder"
Pepper Spray
A defensive irritant spray using the active ingredient Oleoresin Capsicum, the chemical in edible peppers that makes them taste hot, though far more potent in the spray.
Pocket Knife
See "Folder"
"One-handed opening" - A folding knife with some kind of design permitting it to be opened with one hand my means of manually pushing the blade into place with the thumb or in rare cases other fingers. This includes knives with thumb-studs, thumb-holes, or thumb-pads, but does not include switchblades or assisted opening knives. Sometimes called "manual folders" to emphasize the difference from designs with springs.
"Out The Front" - A class of folding knife design wherein the blade slides out of the handle from one end, rather than swinging out of the handle on a pivot. While often used as shorthand for a switchblade that opens in this manner, designs exist that are assisted opening, gravity knives, and manual.
"Swiss Army Knife," a brand of pocket knife, but often used to refer to any of a variety of small non-locking pocket knives with multiple fold-out tools.
Portmanteau of "sheep" and "people." Often a pejorative term for people who don't "get" knives or weapons, and may become frightened by the mere sight of them or otherwise react in an unreasonable manner. Sometimes applied to the demographic of the voting populace that pressure legislators to ban certain weapons on faulty or emotionally-clouded grounds.
A type of knife or dagger with a very slender, almost spike-like blade. Designed primarily as a stabbing weapon. Term is often misused to mean "switchblade" or even "OTF switchblade."
A folding knife where the blade opens by itself using a spring mechanism when the user manipulates a device in the knife's handle, such as a button or slider switch. AKA Automatic knife
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License