A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
This page contains a glossary of various international terms related to fly fishing. Different countries use different words to describe the same thing. (e.g. the US term 'streamer' is not normally used in the UK. We use the word 'lure') We need your help. Please send by e-mail fly fishing words and terms that you use in your country and explain what they mean. We will add them to the list to help other flyfishers from around the world when reading books or tackle catalogs. If you notice any problems or have suggestions for additional definitions that might be useful, please contact me at firstname.lastname@example.org Your help is appreciated.
Club Competition Idea Print this page and use it at your next fishing club meeting to run a competition. Divide your members into teams. Members have to give the correct definition to the fly fishing word given by the quiz master to get a point for their team
A small fatty fin between the dorsal fin and the tail fin
Abdomen The segmented rear section of an insects's body
AFTM The Association of Fishing Tackle Makers (UK based)
AFTMA The American Fishing Tackle Manufactures Association. Its activities include setting technical standards for fishing tackle.
Alevin A recently hatched salmon or trout (also see Grilse, Parr and
Algae Any number of simple plants that contain chlorophyll but lack true roots, stems and leaves.
Amphidromous fish Fish that regularly migrate between freshwater and saltwater for reasons other than spawning, for example to feed or overwinter
Anadromous fish Fish that spend most of their lives at sea but ascend rivers to spawn
Anal fin The fin behind the anus of a fish
Annelid Term used for an aquatic worm which is a common food for trout and other fish.
Antron A synthetic yarn material made of long sparkly fibers used for many aspects of fly tying including wrapped bodies, spent wings, and trailing shucks. Is also used for dubbing material.
Articular The rear bone of the lower jaw of a fish.
- Adipose fin
Back-cast The term used to describe the action of throwing the rod and line backwards, and allowing the line to unroll in the air, before making a forward cast.
Backing Line Nylon or dacron line tied between the flyline and the reel to act as additional line if a longer length than the flyline is required as a reserve to play a big fish.
Badger Hackle A hackle having a black center and white outer fibers, sometimes tipped with black.
Bag Limit The maximum permissible number or weight of fish that can be taken from particular water. Always check local regulations before fishing.
Baiting needle A long needle used for mounting dead fish and other large baits onto terminal tackle.
Bailiff An agent of the land owner who regulates the fishing rights and fishing regulations in relation to a stretch of water. They can in some cases arrest poachers, seize their tackle equipment and catch. They can also prosecute them and take them to court.
Banks The right bank of a river is on your right when you are facing downstream, and the left bank is on the left.
Barb The backward facing projection cut into a hook near the point to reduce the chances of hooked fish escaping .
Barbless hooks Hooks without the backward facing projection cut into a hook near the point. They are easier to get out of the fish and do not cause as much injury. Ideal for catch and release fishing.
Basin A depression in the Earth's surface; the drainage basin of a river system.
Bass bag A canvas or waterproof bag for carrying your catch home in.
Bead Head A Bead Head fly uses a metal bead to simulate the thorax on a nymph or wet fly and to add weight to the fly. Typically gold or silver is used, but any color can be used. Often a bright color such as red can stimulate a fish into biting. In the UK they are known as Gold heads
Beat A term used to describe an area of waterside bank on either a river or stillwater lake, that is allocated to one or more fishermen for their exclusive use over a time period.
Benthic A term describing anything living at or near the bottom of a lake or the sea
Bimini Twist A specific series of knots and twists in a leader which acts as a springy shock absorber in the line, usually used when fishing for large salt water fish.
Biot The short thick barbs from the leading edge of the first flight feather typically from a goose or a duck. Used to simulate tails, legs, antennae and other parts. Can be found dyed in many different colors.
Bi-visiblet A fly with both light and dark colored hackles to give good visibility in both light and shaded water.
Blue Dun Hackle A slate-blue or gray hackle.
Bobbin A tool for holding a spool of thread while fly tying which allows the thread to be dispensed with a controlled tension.
Bonefish flies see Inverted hook Bonefish patterns
Bowfishing Fishing with a bow and arrow. It is permitted on many American waters, and the quarry is usually 'trash' fish such as carp that are competing with more highly prized species such as bass. The arrow is tied to the end of a line and the reel is mounted on the bow. (It is strange that one countries 'trash fish' is another countries highly prized quarry)
Brackish water Water that is slightly salty.
B.s The abbreviation for breaking strain.
Bucktail Hair from a deer's tail
Bulk shot A number of split shot grouped together on a line concentrating weight at a particular point.
Bullet Head Tool A tool with a plate with several holes which can be pushed over the eye of a hook to arrange material in a bullet pattern. The material is first tied in facing forwards beyond the eye symmetrically around the shank, and then pushed backwards by the tool to form the distinctive bullet shape.
Bum bag UK term for a fanny bag (USA fishermen do not use the word 'fanny' if you come for a vacation in the UK. It is US slang for bottom but in the UK it is UK slang for a woman's sexual organ) the word 'bum' in the UK means bottom and not a term for a vagrant.
Butt pad A leather or rubber pad strapped around the waist, into which the end (butt) of a rod is placed so greater leverage can be exerted when fighting large powerful fish. Also known as a rod socket.
Buzzer The common term used to describe Chronomid flies, midges and gnats that hover over the surface of all water..
Freshwater fish that move to the lower river or sea to spawn
- Caddis The term Caddis is used to describe a large diverse family of aquatic insects characterized by down wings. Also the American term for the sedge fly.
- Caenis The scientific name for the broadwing fly, a tiny, pale green insect which hatches in large numbers on summer evenings besides rivers and lakes.
- Cape The neck of poultry or game birds from where hackle feathers are obtained.
- Caudalpeduncle Therelativelyslenderpart of a fish's body between the last dorsal and anal fins and the base of the tail fin (the caudal fin). It is also known as the "wrist" of the fish.
- Chenille A furry rope-like material for making the bodies of artificial flies. The bodies end up looking like a pipe cleaner (with thread in place of the stiff wire). Can be found in many colors and materials, and is a critical component of the Wooly Worm and Wooly Buggers patterns.
- Chironomid Scientific name for the members of the Diptera family of insects commonly known as Midges. In the pupae stage they typically appear to be small aquatic worms.
- Cinch Knot A knot used to tie the tippet to the eye of the fly. A modified version of this, the Improved Cinch Knot, is probably the most used knot for this purpose.
- Cleithrum A bone at the rear of the skull of a fish. It is the main bone supporting the pectoral fin
- Clouser Minnow see Inverted hook Bonefish patterns
- Coarse fish Any freshwater fish of angling interest other than trout salmon, char, grayling, and whitefish.
- Cock Hackles The neck feathers of a cockerel.
- Corixa The name used to describe the lesser water-boatman beetle and the artificial fly that imitates it..
- Cone Head same as a bead head but the bead is cone shaped
- Cover This term describes the action of casting the fly to a fish or into a promising-looking area of water..
- Crazy Charle flies see Inverted hook Bonefish patterns
- Cree Hackle A barred black, red and ginger hackle, sometimes with cream or white flecks.
- Crystal Flash The trade name for a synthetic stringy material used in many streamer patterns to add flash and color.
- Cul-du-Canard Feather Short wispy feathers taken from near the preen gland of a duck. Typically there are few of these feathers found per duck. These feathers add a significant amount of float to a fly due to the fact that they are soaked with natural preen oil. Use of
floatant on these feathers will negate their floating qualities, actually causing the fly to lose flotation.
When a fly has swung around in the current and is directly downstream of the rod it is said to be 'on the dangle'.
- Dapping The art of playing an artificial fly in such a way as to make it look as though it has just fallen on to the water from the branches of bankside trees or other natural obstacles.
- Deadbait Dead fish or other creatures used as bait for predators
- Dead drift A fly-fishing technique in which the fly (dry or wet) is allowed to drift freely along in the current.
- Deer Hair Body hair from deer which is used in many fly patterns to supply body and floatation.
- Delivery An alternative term to 'covering' the term used to describe the action of casting the fly to a fish or into a promising-looking area of water
- Deoxygenation Reduction in the dissolved oxygen content of a water, caused by hot weather or the introduction of pollutants such as sewage. Excessive deoxygenation is fatal to fish.
- Detached body Fly bodies tied not around the hook shank but attached only at the head of the fly as found in Daddy long legs (Crane) Dry flies
- Detritus Accumulated silt and organic debris on the bed of a river or still water
- Dibble The art of attracting fish by skimming and bouncing a wet-fly leader or bushy dry fly across the surface of the water.
- Disturbance pattern A wet- or dry-fly pattern that creates a fish-attracting disturbance when retrieved or worked across the current
- Dorsal fin The fin on the back of a fish, sometimes divided into two or three partly or entirely separate sections. Drainage A drainage basin or a drainage system; the process of draining
- Downstream The direction the current of a river or stream is moving.
- Drainage basin The catchment area of a river system
- Drainage system A river and its tributaries
- Drogue A cone-shaped bag, usually made of canvas, which can be trailed behind a drifting boat to slow it.
- Dropper A short length of leader connected to the main leader with a
- Dry Flies A fly designed to float on the surface.
- Dubbing A primary body ingredient in both dry flies and nymphs, dubbing is a chopped-up fibrous material pinched and twisted onto the thread for wrapping onto the fly. Also refers to the process of applying the dubbing material.
- Dubbing Rake Tool used to tease out dubbing on a fly to give it an enlarged appearance.
- Dun Term used to describe an adult aquatic insect following emergence from the water.
A patch of water that is less disturbed than the surrounding water, found for instance on the edge of a current or where two streams converge
- Electrofishing Passing an electric current through the water to stun the fish, so that they can be collected unharmed for tagging or scientific examination or for relocation to another water.
- Elk Hair Body hair from elk which is used in many fly patterns to supply body and floatation.
- Emerger An aquatic insect in the process of rising to the surface and changing to a flying adult form. Often will have an attached trailing shuck which feeding fish may key upon.
- Estaz Trade name for a chenille which uses colored fine plastic strips for the barbules. Can be found at many craft shops and yarn stores.
- Ethafoam A synthetic material used for making floating flies like a suspender buzzer or nymph
- Euryhaline fish Fish, such as most species of salmon and trout, that can live in both freshwater and saltwater.
A forward casting action used to gauge the ideal distance of real cast, to dry a fly, or to increase the speed of a line.
- False Casting
- Fanny Pack American term for a bum bag. A small bag worn around the waist. The word 'fanny' in the US is slang for bottom and not a woman's sexual organ as in the UK. American fishermen if you go fishing in Ireland or the UK do not use the word 'fanny'.
- Federation of Fly Fishers A non-profit organization dedicated to teaching the sport of fly fishing and the improvement of fisheries.
- Figure-of-eight retrieve A type of line retrieve where the fly line
is bunched in the palm of the hand after being wrapped around the fingures in a
figure of eight retrieve.
- Fighting chair A swivel chair bolted to the deck of a boat from which a big-game angler can fight marlin and other large, powerful fish that can take a long time to subdue. The angler is strapped in by a harness, and either the harness or the chair is equipped with a butt pad or rod socket
- Filter feeder A fish that feeds by filtering plankton from the water.
- Fingerling A small, immature fish, such as a juvenile trout.
- Fish Hair Synthetic hair used in tying streamers and salt water flies.
- Fish ladder A series of interconnected pools created up the side of a river obstruction, such as a weir, to allow salmon and other fish to pass upstream.
- Flashabou Commercial name for a colorful synthetic filament material used in fly tying for adding flash to streamers as well as other
- Flashback A nymph pattern that has a flashy material substituted for
the wing case, such as reflective mylar. Have a look at out Pheasant tail
- Floatant Material applied to flies and leaders in order to cause them to float on the surface of the water. Typically sold in liquid or paste form, although dry shake crystals have recently been found on the market.
- Floss Multi-strand silk or synthetic substitute Material for tying flies.
- Fluorescent Material that emits light of a visible color when ultra violet light falls upon it in the water.
- Fly An artificial lure hand tied with "stuff" on hooks.
- Fly Casting The process of casting a flyline out onto the water.
- Fly Line A weighted line which is cast out onto the water to deliver the fly to the desired location. Can be found in many densities and tapers.
- Floating Line A flyline design to float on the surface of the water along its entire length. Typically used for dry fly fishing and shallow water nymphing.
- (Sinking Line) A flyline design to sink below the surface of the water for getting a wet fly or streamer down deeper. Can be found with different sink rates for different fishing styles.
- (Sinking-Tip Line) A hybrid flyline design which is floating for most of its length except for a short section of sinking line at the end.
- Fly Pattern Recipe used for tying a specific fly.
- Fly Reel A reel used to store line, provide smooth tension, or drag, and to counterbalance the weight of the fly rod during the casting process. Can be found in many different weights and with different drag mechanisms.
- Fly Rod The type of fishing rod used to cast the flyline to the desired position. Historically built with bamboo canes and fiberglass, but now almost exclusively with carbon graphite.
- Fly Tying The process of building fishing flies using thread and various materials.
- Foul-hook To hook a fish anywhere but in the mouth.
- Fresh-run fish A migratory fish, such as a salmon, that has just left the sea and is travelling up a river to spawn.
- Freshwater The water of rivers and most stillwaters, containing little or no dissolved salt
- Fry Very young fish, especially those that have only recently hatched.
A small pouch, on or near the liver of a fish, which stores bile. Bile is a fluid produced by the liver, and aids the absorption of food by the gut.
- Gall bladder
- Gamefish Any fish valued for its sporting qualities
- Gill arch The structure behind the gill covers of a bony fish (or within the gill slits of a cartilaginous fish) that supports the gill filaments and gill rakers.
- Gill filaments The parts of a fish's gills that absorb oxygen from the water.
- Gill rakers Toothlike projections on the gill arches. They can be used to trap food items, such as plankton, carried in the water flowing through the gills.
- Gold Head A Bead Head fly uses a metal bead to simulate the thorax on a nymph or wet fly and to add weight to the fly. Typically gold or silver is used, but any color can be used. Often a bright color such as red can stimulate a fish into biting. In North America they are known as Bead heads
- Golden Pheasant Game bird whose crest, neck and wing feathers are used extensively in fly patterns.
Any soft-stemmed neck feather with non-adhering barbules. Typically used to refer to hen or rooster chicken feathers. Tied to represent the legs of an insect.
- Hatch The time when a large number of nymphs or pupas become fully winged flies, often producing frantic feeding activity among trout.
- Hen Hackle Hackle feathers from a hen chicken characterized by soft, wide feathers. Since these feathers readily soak up water, they are usually used on nymphs and streamers. Jungle Cock A type of hackle with prominent singular white dot patterns often used to suggest eyes. Neck Feathers from the neck of the chicken which are shorter and tend to have a wider selection of sizes on a single skin. Saddle Feathers from the back of the chicken which are longer and have thinner stems. Best choice for most dry flies.
- Herl Feathers used for tying with long individual barbules each having short dense fibers. Used as tails and to make fly bodies. Typically from Peacock and Ostrich.
- Hook Pointed wire hook tied into a fly to catch fish (hopefully).
- Horror flies see Inverted hook Bonefish patterns
A specialized form of angling for fishing through holes cut in the ice of frozen-over waters. The species sought include crappies, walleye, northern pike, pickerel, and perch, and the principal techniques are jigging and tilt (or tip-up) fishing. Jigging involves working a natural bait with a short stick, which has especially shaped handle around which the line is wound. In tilt fishing, the bait is fished static from a rig incorporating an arm or flag that tilts up to signal a bite.
- Ice fishing
- Ichthyology The scientific study of fish and their habits.
- IGFA The International Game Fish Association, based in Fort Lauderdale, Florida. It maintains lists of record fish and also sets technical standards for fishing tackle.
- Introperculum In bony fish, the front lower bone of the gill cover
- Invertebrate A creature that has no backbone, for instance an insect or a worm
- Inverted hook bonefish flies This type of fly was designed so that the hook rode above the shank in the water so that the hook would not get caught on the bottom. By adding relatively stiff wing material near the hook eye which covered the hook point, the fly became nearly weedless. Hooks are dressed to create inversion by bending the hook, by adding weighted eyes on the hook shank opposite the point and/ or by using relatively buoyant materials to cover the hook point. Any of these three techniques can cause the fly to ride inverted. If tied with sparse materials these flies can be made to sink very fast. Bonefish pattern should match the color of the bottom in the area you are fishing. Flies that hit the water with little impact are more effective than those that strike heavy and spook the fish. Clouser Minnow, Horror and Crazy Charlies are all examples of this tying style.
A small artificial lure with a metal head, often dressed with feathers.
- Jigging Fishing by jerking a jig or other bait up and down in the water; an ice-fishing technique
- Jungle Cock An Indian game bird whose hackles have a distinctive cream 'eye' markings. Now illegal to use in the UK and other countries to protect this endangered bird. Artificial material available.
A small ring just above the handle of a fly rod, to which the fly can be hooked when not in use.
- Keeper ring
- Kelt A salmon or trout that has spawned
- Key style tarpon flies These flies are used in clear water where ever tarpon are found and you are sight fishing. A fisherman called Syu Apte was one of the first people to use this design in the 1950's and the Key guides in Florida have used just about every colour combination since.
- Kipper A smoked fish
- Krill Tiny, shrimp like crustaceans, of the family Euphausiidae, that form an essential part of the marine food chain.
Hollow fine plastic tubing wrapped around a hook shank to supply a segmented body.
- Lacustrine A term that describes anything of, relating to, or living in lakes.
- Larva Sub surface stage of development of an aquatic insect.
- Leader Section of line used between the flyline and the tippet. Often purchased as a tapered section, but can be assembled by tying successively smaller diameter sections of monofiliment.
- Lie A quiet or sheltered spot in the water where a fish can rest, hide from predators, or wait for food to come by.
- Limnology The scientific study of lakes and ponds and the plant and animal organisms that live in them.
- Line tray A tackle
tray used to collect the coils of backing or fly line, stopping them from
falling to the ground Normally attached to the fisherman around the waist.
- Livebait Any natural bait, such as a worm, maggot, or small fish,
that is used live
- Loch-style fishing Stillwater flyfishing with teams of wet flies cast a short distance downwind from a drifting boat. Low-water fly A sparsely dressed fly on a small hook, used mostly for salmon fishing in shallow water.
- Loop Connection A method of setting up a flyline/leader rig using loops tied in each section which can be interlocked for easy changing.
- Lures A British word which means the same as the American term 'streamers'. Both describe a type of fly that represent a small swimming fish.
An area of the sea that offers good fishing, usually one that can be located by taking the bearings of shore features.
- Marabou Turkey feather fibers used extensively as wings and tails of lures/streamers
- Marrow spoon A long, slender spoon that can be passed down the gullet of a dead fish to remove its stomach contents. It is used mainly by trout anglers to find out what the fish are actually feeding on at a given time.
- Maxillary The rear bone of the upper jaw of a fish
- Mayfly Term used to describe a common aquatic insect which has a life cycle containing four stages; pupae, larva, dun and spinner. Many, if not most fly patterns are used to imitate this type of insect in its various stages of development. Various species can be found in both moving and still waters, being a staple food in the diet of trout and other fish species. Typically used to refer to the family Ephemerella.
- Mend The term used to describe throwing a loop of line upstream to sink a fly down in the water and avoid drag.
- Milt The semen of a male fish; a term for the semen-filled testes and sperm ducts of a male fish, also known as soft roe
- Mylar Metallic plastic available in sheet or plaited tube form. The tubing can be used to simulate scales on the flanks or fry imitating lures/streamer flies
A knot used to tie together two lines of significantly different diameters.
- Nail Knot
- Nail Knot Tool A tool used to simplify the process of tying Nail Knots.
- Neap tides The tides that occur midway between spring tides. They have smaller rises and falls than those at other times of tire month
- Nictitating membrane A thin membrane that can be drawn across the eyeball to protect and clean it. Found on many fish species, including some sharks.
- Nymph A general term used to describe the subsurface forms of aquatic insects prior to emergence. Also used as the name of flies imitating these insect forms.
The gullet of a fish. Operculum In bony fish, the uppermost and largest of the gill cover bones
- Osmosis The process by which a fish takes in or excretes water through its skin in order to maintain the correct balance of salts and fluids within its body tissues.
- Otoliths Oval, stone like structures within the ears of a fish or other vertebrate, which help it to maintain its balance; they are also known as ear stones.
- Ova The eggs of a fish or other creature. The mass of eggs within the ovarian membranes of a female fish is termed hard roe
- Ovaries The reproductive glands (gonads) of a female fish, which are responsible for the production of eggs
- Oviducts The ducts between the ovaries and vent in most female fish, along which the ripe eggs pass during spawning.
- Oviparous fish Fish that lay eggs from which the young later hatch. All skates, some sharks and rays, and most bony fish are oviparous
- Ovoviviparous fish Fish whose eggs are fertilized and hatched within the female's body. The eggs are enclosed in separate membranes and the embryos within them receive no nourishment from the mother. Most sharks and rays are ovoviviparous
A method for wrapping a hackle feather over a section of the fly's body. When it is retrieved through the water it 'pushes' the water and this causes attractive movement shock waves that help fish locate the fly.
- Panfish Any small American freshwater food fish, such as a sunfish or perch, that is fished for by anglers but is too small to be considered a true gamefish
- Parabolic-action rod Another term for a through-action rod.
- Parachute fly A dry fly with its hackle wound in the horizontal plane to help it float on the surface of the water and land softly so as not to spook the fish.
- Pattern The fixed design of material and position of parts which make up an artificial fly sometimes called its recipe.
- Parr Young salmon and trout up to two years old, distinguishable from smolts by the dark bars (parr marks) on their sides
- Peacock Sword A feather from a peacock with bushy herl-like barbules, commonly used for tails.
- Pectoral fins The pair of fins just behind the head of a fish.
- Pelagic fish Fish that live at the surface, in the upper waters, of the open ocean
- Pelvic fins The pair of fins on the lower body of a fish; also called ventral fins.
- pH The pH number of a liquid, such as water, indicates its acidity or alkalkdty. Pure water has a pH of 7; water with a pH of less than7is acidic, and water with a pH of more than 7 is alkaline. Acid rain typically has a pH of less than 5.
- Pharyngeal teeth Teeth at the back of the throat, found in many fish species such as the members of the carp family. These teeth crush food as it is swallowed
- Pisciculture The breeding and rearing of fish, for example in hatcheries and fish farms. Pool A relatively wide, rounded area of a river, usually found just downstream of fast, narrow run
- Point The finely tapered end-section of a fly cast, or the fly at the tip of the fly cast.
- Point Fly The lead fly in a two fly rig. Usually a section of tippet is tied to the eye or the bend of the hook to connect to the dropper fly.
- Polyshoot Backing A
smooth, flexible non-tangling backing for shooting lines.
- Poly Yarn A synthetic yarn made from polypropylene. Used in fly tying, often for parachute posts and wings on dry flies.
- Potamodromous fish Fish that migrate regularly within large freshwater systems
- Predatory fish Any fish that prey on other living creatures, particularly other fish.
- Premaxillary The front bone of the upper jaw of a fish
- Preoperculum In bony fish, the bone at the rear of the cheek, just in front of the gill cover
- Pupa Sub-surface larval stage of aquatic insect development.
- Pyloric caeca Fleshy, fingerlike tubes at the junction between the stomach and intestine of a fish. They produce enzymes that play a part in the digestive process.
The bone that joins the upper jaw of a fish to its skull
The soft or spiny supporting elements of fish fins.
- Redd A hollow scooped in the sand or gravel of a riverbed by breeding trout or salmon as a spawning area.
- Retrieve The recovery of a cast fishing line by pulling it in, by one means or another.
- Reversed-taper handle A rod handle that tapers towards the butt end.
- Riffle A small rapid in a river or stream (see also Eddy, Pool, Run, Scour, Slack).
- Riparian A term that describes anything of, inhabiting, or situated on a riverbank; often used in connection with ownership and fishing rights.
- Rip-rap Broken rock, deposited loosely on a riverbed or on the banks to help prevent erosion. It is also used to form breakwaters and embankments.
- Rise The action of a fish coming to the surface to take an insect; the taking to the air of a large hatch of mayflies or other insects on which trout feed (see also Hatch).
- Rod Socket See Butt pad
- Roe A collective term for fish milt and ova
- Roll-cast The method of casting the fly from the side, when there is now room behind you for a back-cast.
- Run A fast-flowing stretch of river; the movement of fish inshore or upstream for spawning; the flight of a hooked fish trying to escape; a small stream or brook.
The level of dissolved salts in the water. Freshwater normally contains less than 0.2% salts, brackish water contains up to 3% salts, and saltwater (such as seawater) more than 3%. Normal seawater contains 3.433% salts - 2.3% sodium chloride (common salt), 0.5% magnesium chloride, 0.4% sodium sulphate, 0.1% calcium chloride, 0.07% potassiumchioride, and 0.063% other salts.
- Saltwater Water containing a high level of dissolved salts.
- Scour Erosion caused by flowing water; a shallow, fast-flowing, gravel-bottomed stretch of river.
- Scud Term used for freshwater shrimp.
- Sea Trout A migratory brown trout
- Sedges Waterside plants or flies which belong to the Trichoptera order of insects.
- Seducer flies This pattern is like the Key Style fly but the long hook shank is covered with palmered hackle, left upright to be less streamlined and create more disturbance in the water. It also has the attribute of falling to the surface more quietly and not spooking jumpy fish. It is also ideal for redfish, striped bass, snook and other species that prefer slow moving undulating flies with great action at slow speeds. Homer Rhodes is credited with developing this type of fly in the 1950's
- Seminal vesicle A small gland that adds nutrient fluid to the milt of a male fish during spawning
- Shooting Head A shorter fly line with a heavy belly section used to
gain extra distance..
- Sink-and-draw A method of fishing in which the lure, fly, or bait is made to rise and fall alternately during the retrieve by raising and lowering the rod tip.
- Sinkant A liquid applied to flies to make them sink.
- Sink-tip A floating fly line with a sinking tip, used to fish flies just below the surface. Slack Tidal water where there is little surface movement during the interval between the ebbing and flowing tides; a stretch of river with very little current, for instance above a weir.
- Slip A narrow strip of feather. Slips are widely used in fly tying.
- Smolt A young salmon or sea trout, silver in color on its first journey to the sea.
- Spinner A spent adult aquatic insect following laying its eggs on the surface of the water.
- Spring tides The tides that occur around the time of full and new moons. They have larger rises and falls than those at other times of the month.
- Steelhead A migratory rainbow trout
- Streamer flies An American word for the British term 'Lure'. It describes flies that imitate small swimming fish.
- Stock Fish fish that are reared in captivity and stocked into fisheries are known as 'stock fish'.
- Stonefly Family of aquatic insects commonly imitated in flyfishing. Many species are found in western streams.
- Strike To tighten the line to set the hook when a fish bites, usually by raising the rod tip or lifting the rod.
- Strip The term used to describe taking in the line by hand, as opposed to reeling it in.
- Suboperculum In bony fish, the rear lower bone of the gill cover.
- Supracleithrum A bone at the upper rear of the skull of a fish. It is one of the bones that support the pectoral fin.
- Surface film The apparent elastic like film on the surface of water, which is created by surface tension.
- Surface tension The natural tendency of the surface of water (and other liquids) to behave like an elastic sheet. It is caused by forces acting between the water molecules: the molecules at the surface are much more strongly attracted to each other, and to the molecules below them, than they are to the molecules of air above them.
- Swim The stretch of a river, or the part of a pond or lake, that is being fished in at a particular time.
The short, thick tail on an artificial fly, generally made out of silk or colored filaments of nylon.
- Take The action of a fish in picking up or grabbing a bait or lure.
- Tandem fly A fly consisting of two or more in line hooks connected by a short length of strong line.
- Taper The narrowing in diameter, from butt to tip, of a rod, and the narrowing of the end section of a fly line. The rate of taper determines the action of the rod or line.
- Tarpon Flies There are basically three types of Tarpon Streamer flies: (see Keys style, Seducers and Whistlers.)
- Terrestrial Term used to describe land-based insects which are often food for fish
- Terminal tackle The tackle, including the hook or lure, attached to the end of the reel line (main line).
- Thorax The front portion of the body of an insect to which the wings and legs are attached.
- Tighten The act of rising the rod tip quickly to straighten the line and apply tension to it, in order to sink the hook into the mouth of a taking fish.
- Tilt fishing A technique used in ice fishing; is also known as tip-up fishing
- Tinsel A metallic filament used in fly tying to provide flash and color.
- Tippet The thin end section of a fly leader, to which the fly is tied. Also a term used for a small orange and black barred feather from the Golden Pheasant game bird
- Trailing Shuck A section of synthetic yarn tied to the back of a fly to imitate a case being shed from an emerging insect.
- Troll The term used to describe the action of towing a fly behind a boat.
- Trout Unlimited Non-profit organization dedicated to the protection and improvement of trout fisheries, with an emphasis towards wild trout.
- Tube fly An artificial fly consisting of a metal or plastic tube, dressed with feathers, hair or other materials and threaded onto the line. The hook, usually a treble, is then attached to the end of the line.
- Undercurrent The flow of water beneath the surface which can be
opposite the surface flow on stillwaters..
- Upstream Against the current of the river or stream.
- Upwing flies The The Ephemeroptera order of flies, whose wings are nearly vertical and who possess two or three tails or setae.
- Upwind Into the wind
The duct that carries sperm from the testis of a spawning male fish
- Vas deferens
- Vent The anus of a fish. It is also the orifice through which a spawning female fish lays her eggs (or, in the case of a viviparous fish, gives birth) and through which a male fish discharges his milt during spawning
- Ventral fins See Pelvic fins
- Vertebra An individual segment of the backbone of a fish.
- Vertebrate A creature that has a backbone, for instance a fish or a mammal
- Vest A piece of clothing used to hold various tools, fly boxes and other equipment while fishing.
- Vise The tool used to hold a hook in place while tying the fly.
- Viviparous fish Fish whose ripe eggs are fertilized and hatched within the female's body; they give birth to live young. Unlike those of ovoviviparous fish, the developing embryos receive nourishment from the mother. Some sharks and some bony fish, such as surf perch, are viviparous
- Vomerine teeth Teeth on the vomer, a bone at the front of the roof of the mouth of bony fish
Protective outer clothing used to keep the fisherman dry when standing or float-tubing in water. Typically made of neoprene, nylon, or a Goretex-like material. Can be insulated to supply warmth.
- Wake fly A dry fly that creates a splashy, fish-attracting wake when pulled across or through the surface of the water.
- Wet Fly An artificial fly designed to swim beneath the surface.
- Whip Finish A knot used to tie off the thread when finishing a fly.
- Whip Finishing Tool A tool designed to make whip finishing quick and easy.
- Whistler flies These are used after dark, in deep water, or where visibility is not very good. The large bead-chain eyes and the bulky dressing, create underwater vibration. The bead-chain eyes make the fly dip every time the angler pauses on the retrieve. This gives the fly a jigging motion on the retrieve. It was developed by American West Coast Fly fisherman Dan Blanton. The large wing and bulky body generate sound waves in low-visibility water so tarpon and other species can find it.
- Windward The direction the wind is blowing
- Wobbling A freshwater spinning technique using a lure, or a small, dead fish mounted on treble hooks, for bait. The bait is cast a long way out and retrieved in an erratic fashion by making side4o-side movements of the rod tip and at the same time varying the speed of the retrieve.
The membrane-covered food pouch found on the belly of a newly hatched fish. It nourishes the growing fish until it is able to feed itself.
- Yolk sac
A retractable string clip used to connect tools to ones fly vest.
- Z-Lon Trade name for a synthetic yarn used in making carpeting. Can be used for many purposes in fly tying such as nymph bodies, spent wings, and trailing shucks.