Glossary
Every term, in plain English.
103 entries. Tap any term to see the short definition; entries are linked everywhere they appear inside FishCast water reports.
Hatches 16
- BWOA small mayfly with smoky-blue wings and an olive body, hatching cool and overcast from spring through fall.
- CaddisAn aquatic insect with a tent-shaped wing posture as an adult. Behaves more erratically than a mayfly on the surface — fish key on motion when caddis are on the water.
- CallibaetisThe most important still-water mayfly. Hatches on lakes and slow backwaters spring through fall in two or three broods per year. Spinners cluster over the water at dusk; the spinner fall is the prime hour.
- DunThe first winged adult stage of a mayfly, riding the water as it dries its wings before flying off. The phase trout key on during a mayfly hatch.
- Golden StoneA medium stonefly — yellow-amber body, sizes 6–12 — that follows the salmonfly hatch on Western rivers. Less spectacular but longer-lasting than its bigger cousin.
- Green DrakeA large early-summer mayfly hatch — sizes 8–12, bright green body. The biggest dry-fly targets of the year on Western rivers.
- HatchWhen aquatic insects emerge from the water as adults, often in a tight time window. Fish gorge during hatches and key on whichever bug is most abundant.
- HendricksonA mid-spring mayfly hatch — pinkish-brown body, dark gray wings — that signals the start of dry-fly season on Eastern and Midwestern rivers.
- MayflyAn aquatic insect with an upright wing posture as an adult. Most North American fly hatches center on mayflies.
- MidgeA tiny mosquito-like insect that hatches year-round. The smallest commercial midge patterns go down to size 28 — a serious cold-water and tailwater staple.
- PMDPale Morning Dun — a mid-summer mayfly hatch on Western tailwaters. Light yellow body, peak emergence late morning into early afternoon.
- SalmonflyA massive stonefly — bodies up to 2 inches — that hatches in early summer on Western rivers. The biggest dry-fly target of the year when it's on.
- SulphurA pale yellow-orange mayfly hatch on Eastern rivers, emerging late afternoon through dusk in May and June. Rivals the BWO for time on the water.
- Trailing ShuckThe empty nymph case still attached to an emerging adult mayfly, dragging behind it in the surface film. The "stuck halfway out" silhouette that trout key on during heavy hatches.
- TricoA tiny black-bodied mayfly that hatches in massive clouds at dawn, late summer through fall. Sizes 22–26 — the smallest commercially-tied dries.
- Yellow SallyA small yellow stonefly — sizes 12–16 — that hatches throughout the summer on Western rivers. Often overshadowed by bigger hatches but reliably brings fish to the surface.
Flies 30
- CDC EmergerAn emerger pattern using CDC (Cul de Canard) feathers as the wing, which trap air bubbles and float at the same level as a real emerging insect.
- Chernobyl AntThe original big foam attractor dry — layered foam, rubber legs, sometimes a parachute post. Imitates nothing specific, eats like a hopper or stonefly, floats like a cork. Started the "junk dry" revolution.
- Chubby ChernobylA buoyant foam-bodied attractor with rubber legs and a high-vis post. Imitates a hopper, salmonfly, golden stone, or "general big bug" — and floats a heavy nymph below it.
- Clouser MinnowBob Clouser's lead-eyed streamer with a sparse bucktail body. Rides hook-up because of the weighted eyes — snag-resistant, sinks fast. The universal warmwater and saltwater streamer.
- ComparadunA mayfly dun pattern with a fanned deer-hair wing and no hackle. Sits low in the film like a real adult, ideal for picky fish on flat water.
- Copper JohnA heavy attractor nymph with a copper-wire body and a tungsten bead head. Sinks fast; flashes in deep water. The standard "anchor fly" in indicator and Euro nymph rigs.
- Dry FlyA fly designed to float on the surface, imitating an adult insect. The visual takes are why most fly anglers fish dries even when nymphs catch more fish.
- Elk Hair CaddisA buoyant dry fly tied with elk hair as the wing — imitates an adult caddisfly. Floats like a cork; ideal for fast water and skating presentations.
- EmergerA fly imitating an insect transitioning from underwater nymph to winged adult. Floats in or just under the surface film, matching trout that are eating in that exact window.
- FrenchieA high-attractor pheasant-tail variant with a hot-pink or chartreuse collar, slim profile, and tungsten bead. The go-to Euro-nymph "junk" fly — the bright collar triggers reaction strikes in fast water.
- Hare's EarA general-purpose buggy nymph tied with hare's-mask dubbing and a gold rib. Imitates mayfly nymphs, caddis pupae, and "something edible underwater."
- HopperA terrestrial dry fly imitating a grasshopper — foam-bodied with rubber legs, sized 8-14. Late-summer staple anywhere grass meets water. Often fished as the buoyant indicator of a hopper-dropper rig.
- Muddler MinnowDon Gapen's original sculpin imitation with a spun deer-hair head, mottled turkey wings, and a flashy tinsel body. Versatile — dead-drifted as a hopper, swung as a streamer, or stripped fast as fleeing baitfish.
- NymphAn underwater fly that imitates an insect larva or pupa, fished below the surface where most trout do most of their feeding.
- Parachute AdamsA general-purpose dry fly with a parachute hackle and a high-vis post. Imitates almost any mayfly dun and is the single most-fished pattern in trout fly fishing.
- PerdigonA slim, heavily weighted Spanish nymph with a tungsten bead, lacquered body, and minimal materials. Built to sink fast in heavy water — the Euro nympher's depth-finder fly.
- Pheasant TailA small brown nymph imitating mayfly nymphs. Tied with pheasant-tail fibers for the body and a wire rib. The most-fished nymph pattern in trout fishing.
- Prince NymphAn attractor nymph with a peacock-herl body, brown goose-biot tail, and white biot wings. Doesn't imitate any specific bug — trout eat it everywhere. A standard searching nymph.
- RS2Rim Chung's lightweight emerger pattern — a slim wisp of synthetic fibers suggesting a mayfly transitioning out of its nymphal shuck. Tied in olive, gray, or BWO and fished just under the film.
- San Juan WormA simple chenille fly imitating an aquatic worm or freshly dislodged earthworm. Hot pink, red, or rust is standard. Effective year-round and especially after rain, when real worms wash into the river.
- SculpinA streamer imitating a sculpin — a small, bottom-dwelling baitfish that big trout key on. Heavy, big-headed, dragged or swung along the bottom.
- Soft HackleA traditional wet-fly style with a soft webby hen or partridge hackle wound at the head. Pulses on the swing and reads as an emerging caddis, mayfly, or generic "something rising." Old-school, devastating in a hatch.
- Sparkle DunA low-floating mayfly emerger with a deer-hair wing and a sparkly Z-Lon trailing shuck. The pattern tied to selective fish feeding in the surface film.
- Spent WingA fly tied with the wings flat and spread out to imitate a dead mayfly spinner. Used during spinner falls when adult mayflies have died and lie flat on the surface.
- StimulatorAn attractor dry fly with an elk-hair wing and palmered hackle. Imitates stoneflies, caddis, and big mayflies all at once. Floats high; takes abuse.
- StreamerA larger fly imitating a baitfish, leech, or small mammal. Stripped or swung; targets aggressive predatory feeding rather than rising fish.
- WD40A tiny midge and baetis emerger (sizes 18-24) tied with mallard fibers for a tail and wing case over a thread body. The tailwater go-to for selective trout sipping in the film.
- Wooly BuggerA general-purpose streamer with a marabou tail and a chenille body. Imitates everything from a leech to a small baitfish — the streamer equivalent of "tie one on and start fishing."
- Zebra MidgeA tiny pupa-imitating nymph — silver wire ribbed body, tungsten bead head — for fishing midge hatches and cold-water tailwaters year-round.
- ZonkerA weighted streamer with a rabbit-strip wing that pulses and breathes like a real baitfish. The rabbit strip — thin tanned hide with fur attached — gives it more action per inch than almost any synthetic.
Lures 12
- CrankbaitA hard-bodied diving lure with a lip on the nose. The lip controls how deep it runs and how it wiggles on retrieve — square-bills bounce off cover shallow, deep-divers crank down to 15+ feet.
- Inline SpinnerA small spinning lure with a single blade rotating around a straight wire shaft, weighted body, and treble hook at the back. Mepps, Rooster Tail, and Panther Martin are the classics.
- JigA weighted hook with a soft-plastic body or hair-tied skirt. The most-fished lure type for warm-water and cold-water species alike.
- KastmasterAcme Tackle's signature casting spoon — a four-sided wedge of solid brass with a balanced wobble. Casts a country mile against the wind and runs deeper than thin spoons. Trout, salmon, bass, pike, surf — universal.
- Little CleoAcme's curved trolling and casting spoon — wider belly than a Kastmaster, more pronounced wobble at slower speeds. Standard for stillwater rainbow trout, Great Lakes salmon, and slow-trolled walleye.
- NightcrawlerA large earthworm (Lumbricus terrestris), 4-8 inches long, used live as the deadliest universal trout, panfish, and bass bait. Bigger and tougher than garden worms; hooks well and survives multiple drifts.
- PowerBaitBerkley's brand-name floating dough bait designed for stocked stillwater trout. Molds onto a small treble; the buoyant dough floats the hook off bottom and into the cruising lane of stocked rainbows.
- RapalaLauri Rapala's hand-carved balsa minnow plug from 1936 — the original neutral-buoyancy crankbait. Floats at rest, dives a few feet on retrieve, twitches with an injured-minnow wobble. Every modern minnow plug imitates it.
- Salmon EggsReal or cured salmon and trout roe, fished as single eggs, clusters, or roe sacks. The deadliest steelhead and salmon bait — and a top trout bait wherever stream eggs naturally occur.
- SpinnerbaitA safety-pin shaped lure with one or two spinning blades on the top wire and a weighted hook with a silicone skirt on the bottom. A bass classic — different beast from the inline spinner despite the shared name.
- SpoonA curved metal lure shaped like the bowl of a spoon. The curve makes it wobble and flash on retrieve, mimicking a fleeing or injured baitfish.
- SwimbaitA soft-plastic or jointed hard lure that imitates a swimming baitfish. The tail kicks side-to-side on retrieve, producing a profile and wake closer to a live minnow than a spinner or crank.
Technique 15
- Back-CastThe half of the cast where the line travels behind you. Has to fully straighten before you start the forward cast or the line collapses.
- Carolina RigA bottom-contact rig where a heavy bullet weight slides on the main line above a swivel, with a 12-36 inch leader and bait/soft plastic trailing behind. The weight stays on bottom; the bait drifts a few feet up in the water column.
- Dead driftA presentation where the fly travels at the exact speed of the current, with no line tension pulling it sideways.
- DragWhen current tension on your line pulls the fly across the water faster or slower than the natural drift, alerting the fish.
- Drop ShotA finesse rig with the hook tied above the weight on the same line. The weight sits on bottom, the bait suspends at a fixed distance above — usually 6-18 inches — and shakes in place when you twitch the rod.
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- HaulA pull on the fly line with the off-hand during the cast, accelerating the line and adding distance. Single haul on the back- or forward-cast; double haul on both.
- HooksetThe action of driving the hook into a fish's jaw after a strike. Different gear and presentations call for different sets — vertical, sideways, or strip-set.
- MendA flick of the rod tip after the cast to reposition slack line on the water and let the fly drift naturally.
- PresentationHow the fly arrives, drifts, and looks to the fish. A perfect fly with a sloppy presentation catches fewer fish than a wrong fly fished cleanly.
- Spey CastA family of fly-casting techniques that use the water's tension on the line to load the rod, requiring no backcast. Originated on Scotland's River Spey for steelhead-style fishing in big rivers with brush behind you.
- StripTo pull line in by hand with the off-hand, retrieving the fly. Strip cadence (speed plus pause) controls how the fly behaves underwater.
- Surface FilmThe thin layer of water at the air-water interface, held together by surface tension. Mayfly and caddis emergers struggle through this barrier to reach the air — and trout key on the vulnerable seconds when bugs are stuck halfway through.
- SwingA presentation where the fly drifts across the current at the end of the cast, riding the bowing line. Particularly effective on streamers and wet flies.
- Tag EndThe short length of line left over after tying a knot — the part you trim off. The other end (the one going to your reel) is the standing line.
Reading water 13
- CurrentThe flow of water in a stream or river. Speed, direction, and depth determine where fish hold and how food drifts past them.
- EddyA pocket of water where the current circles back on itself, creating slack on the inside of bends or behind structure. Fish use eddies to rest and feed without fighting current.
- Feeding LaneA narrow corridor of current where food consistently drifts past — usually a foot or two wide. Active fish stack along feeding lanes.
- FreestoneA river fed by snowmelt, rain, and tributaries — flows swing wildly with weather and season. Bigger-fly water; opportunistic fish; rocky channels.
- Holding WaterWater that fish actively use to rest and conserve energy — slack pockets behind structure, deep pools, slow seams.
- LieA specific spot in the water where a fish holds — usually combining a current break, a food lane, and overhead cover.
- PoolA deep, slow stretch of stream where fish hold to rest and conserve energy. The bottom of a riffle is often the head of a pool.
- RiffleA shallow, broken-surface stretch of river where current accelerates over a rocky bottom — the most oxygenated and bug-rich water on a stream.
- RiseA trout taking food off the surface, leaving a visible disturbance. The form of the rise (splash, sip, dimple) tells you what stage the fish is eating.
- RunFaster water between a riffle and a pool. Often the most consistent dry-fly water — fast enough to keep food drifting, slow enough for fish to hold.
- SeamThe boundary between fast and slow water — often where a riffle dumps into a flat. Fish hold on seams to eat without fighting current.
- StructureAnything in or above the water that creates a current break, holds fish, or provides cover. Boulders, downed trees, undercut banks, depth changes.
- TailwaterA river section directly below a dam. Cold, clear, regulated flows; trout grow large because feeding rarely shuts off. Different rules than a freestone.
Gear 10
- BobberA buoyant float on the line that suspends bait at a set depth. Fixed bobbers sit in one spot; slip bobbers slide up to a stopper for adjustable depth.
- Fly BoxA plastic or aluminum case for organizing flies. Slotted foam, magnetic, or compartments — the angler's portable selection.
- Fly LineA heavy, plastic-coated line that loads the rod on the cast. Comes in floating, sinking, and intermediate densities; rated by weight (3wt–12wt) to match your rod.
- Fly RodA long, flexible rod (usually 7–10 feet) designed to cast the weight of fly line — not the weight of the fly. Sized by line weight (3wt, 5wt, 8wt) to match the fishing.
- IndicatorA floating attachment on the leader that signals when a fish takes a sub-surface fly. Like a fly-fishing bobber, but lower-profile and tunable for depth.
- LeaderA tapered length of monofilament between the fly line and the fly. The taper transfers energy from the cast smoothly so the fly lands gently.
- ReelThe mechanical device on the rod that holds line and lets fish run against drag. Different designs for fly, spin, and bait — but all do the same job.
- Split ShotA small lead (or tin) weight pinched onto the line above the hook to sink bait or a fly to fish-holding depth.
- SwivelA small two-eye metal connector that lets the line above rotate independently from the leader below. Stops line twist from spinning lures and locks a sliding sinker above the leader on bottom rigs.
- TippetThe thin, nearly invisible final section of a fly leader that ties directly to the fly. Sized in numbered "X" classes — higher X = thinner.
Knots 6
- Blood KnotA streamlined knot joining two pieces of similar-diameter line. Used to build tapered leaders or splice tippet sections without the bulk of a Surgeon's Knot.
- Egg Loop KnotA loop-style snell knot tied around the shank of a hook so a soft bait (single salmon egg, sand shrimp, cluster of eggs) can be pinched into the loop and held in place without piercing the bait.
- Improved Clinch KnotThe standard knot for tying line to a hook eye. Five to seven wraps of the tag around the standing line, back through the small loop, then back through the big loop. The 'improved' step keeps it from slipping on small hooks.
- Loop KnotA knot that creates a small open loop at the tippet-to-fly connection, letting streamers, articulated patterns, and big bugs swing freely instead of locking to the line.
- Nail KnotA streamlined knot joining a butt section of monofilament leader to the fly line itself. Slides through rod guides cleanly; doesn't unravel.
- Surgeon's KnotA simple knot for joining two pieces of line of similar diameter — typically tippet to leader. Two overhand knots on doubled line; ties in 8 seconds in the cold.