1) a bent piece of wire with its tip sharpened and often a barb below the tip, used to catch fish. Available in many sizes and styles, variously numbered and named. May be single, double or treble but all these are counted as one hook in angling regulations. Hooks separated by stretches of line are counted as multiple hooks. Bronze hooks are favoured for live bait fishing as swallowed hooks will dissolve in digestive juices if they cannot be removed without harming the fish. A hook comprises an eye (a circular bend at one end for line attachment), a shank (the long straight part, may be long- or short-shanked, depending on types of bait used, rounded (regular) or flattened (forded)), a bend or shape (the curved part), the spear, spearhead or point (the straight part after the bend), the point (the end of the hook) and a barb behind the point. The distance between the point and the shank is the gape or gap and the distance between the lowest part of the bend and the gape is the throat or bite. There are various forms of the eye of a hook, the ball or ring eye being the most common. Others include tapered, needle, hole, brazed, looped, loose, open straight, open cut, open bent aside and koohto. The eye itself may be straight (in line with the shank), turned down or turned up. Some hooks do not have an eye but a flattened end to which line must be whipped or snelled rather than tied. Flattened ends come in various patterns such as straight, marked, tapered, marked tapered, spaded and knobbed. Each hook pattern has a normal shank length, varying between patterns, and many patterns come in a variety of shank lengths. While most shanks are straight, they can be bent in various ways. Bent patterns include bent back, bent down, tipped back, bent aside, curved, kinked, stepped, crimped popper, Swedish dry fly, flybody, sedge and flat-body nymph, all variously directed to penetrate efficiently or to hold particular baits. A humped shank is to prevent cork, plastic, wood or rubber bodies from turning around on the shank, a sliced shank has barbs to attach a worm, egg or other bait, a curved down one is made to bring the line of pull closer the the line of point penetration and a central draught shank is bent upward for a quick and raking penetration. Names of gapes and bites include English Bait, Aberdeen, Siwash, Trout Italien, Pike and Wide Bend. The pike has a very wide gape, for example, to hold a large bait, hook a long-snouted fish and in in setting the point behind a long jawbone. The point comes in various forms, such as spear, hollow, rolled, Dublin, knife, barbless needle, barbless humped and harpoon. The bend can be kirbed (offset to the right when viewed from the top of the hook with the eye towards the observer), straight or reversed (opposite of kirbed, bent to the left), the shank can be in various lengths and cross sections, and the diameter of the wire the hook is made of can vary significantly. The hook\'s pattern is usually based on the shape of the bend and named types include Carlisle, O\'Shaughnessy, Eagle Claw, Beak, Kirby, Model Perfect, Aberdeen, Siwash, Limerick, Sproat, Sea Mate and Albacore. Eyes may be ball (a circle perpendicular to the plane of the hook; closed, tempered and strong or open and not as strong or expensive), tapered (the eye and shank nearby are tapered to make the hook lighter for dry fly-fishing), looped (the eye runs back along the shank and may be tapered; found in salmon wet flies), needle (shaped like a needle eye, easily used with a natural bait), brazed (the eye gap is brazed to the shank ensuring the leader will not be cut and for strength; found in big-game hooks), or flattened (the shank is pierced, used for medium-sized species in commercial fishing). Eye positions may be ringed (parallel to the shank, used with lures in tandem), turned up (gives more clearance between the shank and point for fully dressed flies) or turned down (closer to the line of penetration). Types of points include needle (best penetration but easily blunted), hollow (rounded out between barb and tip for fast penetration), spear (more easily made than the preceding, varies types and not as penetrating as the preceding), barbless, arrow (does not penetrate easily, rarely used), and knife-edge (very sharp with all four sides ground, flattened and difficult for a big-game fish to throw). The point position may be straight (parallel to the shank), rolled or rolled-in (bent in towards the shank), bent-in (whole spear bent in towards the shank giving a small bite but difficult for the fish to eject), and bent-out (bent out away from shank for quick penetration). The various types and shapes of hooks can be seen in angling books and sales catalogues
Dictionary of ichthyology. 2009.