Fish Terms


Showing 322 items
TermMeaning / ExplanationAdditional RemarksCategory
TermMeaning / ExplanationAdditional RemarksCategory
Abdomen Belly; lowest part of fish body  Fish Anatomy 
Abyssal zone Region of the ocean floor between the depths of 4000 and 6000 meters  Habitat 
Abyssopelagic Pelagic zone between the depths of 4000 and 6000 meters   Habitat 
Actinosts Series of bones at the base of the pectoral rays  Fish Anatomy 
Acuminate Tapering gradually to a point  Description 
Acute Pointed; Sharp  Description 
Adipose eyelid Transparent fleshy tissue covering part or all of the eye in some fishes  Fish Anatomy 
Adipose fin Small fleshy fin-like projection on the back between the dorsal fin and the caudal fin Only on some fishes Fish Anatomy 
Adnate Joined together  Description 
Adpressed Pressed close to or lying close against body  Description 
Aestivate Dormant or inactive during dry period  Biology 
Affluent A stream or river that flows into a larger one; a tributary  Habitat 
Airbladder A gas-filled sac lying under the backbone in the abdominal cavity, used in buoyancy Also referred to as swimbladder or gasbladder  Fish Anatomy 
Anadromous Living mostly in salt water and migrating to spawn in fresh water  Biology 
Anal Pertaining to the anus or anal fin  Fish Anatomy 
Anal fin Lower fin on the belly behind the anus  Fish Anatomy 
Angler A person that uses a fishing rod and reel to catch fish  Fishing 
Angling Recreational catching of fish with hook, bait, line and fishing rod or pole  Fishing 
Ankylosed Grown firmly together  Description 
Antennae Paired feelers on the head of crustaceans  Other 
Anterior Pertaining to the front portion  Description 
Anti-reverse Fishing reel mechanical system that prevents the reel from spinning in reverse rotation and causing tangles Fishing equipment term Fishing 
Antrorse Turned forward  Description 
Anus Vent; opening of the intestine through which wastes are excreted  Fish Anatomy 
Archipelago A group of islands; an expanse of water with scattered islands  Habitat 
Arthropods Member of Phylum Arthropoda having a hard exoskeleton and jointed legs; includes insects, crustaceans, and arachnids  Biology 
Asperity Rough edge on a surface  Description 
Asymetrical Not symmetry  Description 
Attenuate Tapering to a point  Description 
Attenuate Elongate; extended or drawn out  Description 
Attractant Scent additive applied to fishing lures to attract fish  Fishing 
Axil Angular area between pectoral fin and body  Fish Anatomy 
Axillary scale An elongate or modified scale at the insertion of the pelvic or pectoral fins Only on some fishes Fish Anatomy 
Backlash A tangle or snarl in the fishing line cause by overrun spool  Fishing 
Backwater An area of a river that is sometimes isolated  Habitat 
Bail arm A semi circular part of a fishing reel that guides the line on the spool Fishing equipment term Fishing 
Baitrunner A fishing reel with more than one drag settings that can be switched  Fishing 
Band An oblique or irregular marking Marking Description 
Bar An elongate nearly straight vertical marking Marking Description 
Barb A sharp projection on the fishing hook that holds a hooked fish Fishing equipment term Fishing 
Barbel Fleshy whisker-like projection, usually under the mouth  Fish Anatomy 
Basal Pertaining to the base  Description 
Base of fin The part of the fin that attaches to the body  Fish Anatomy 
Bathyl Zone Region of the ocean floor between the depths of 1000 and 4000 meters  Habitat 
Bathypelagic Pelagic zone between the depths of 1000 and 4000 meters   Habitat 
Bay Indentation in the shoreline of a river, lake or other body of water  Habitat 
Bayou A marshy outlet of a lake or river  Habitat 
Benthic Refer to to the ocean bottom; bottom-dwelling; living on the sea bed  Habitat 
Benthopelagic Living in the waters above but near the bottom  Habitat 
Blind Side The side of a flatfish that does not have any eyes  Fish Anatomy 
Bobber A float attached to the line to hold the bait or lure at a predetermined depth and act as a strike indicator  Fishing 
Bottom fishing Fishing with the hook placed close to the water bed for benthic fish  Fishing 
Brackish Mixed fresh and marine water  Habitat 
Branchiae The gills of fish and some invertebrate animals  Fish Anatomy 
Branchial aperture Gill opening  Fish Anatomy 
Branchiostegal rays Bony rays supporting the membranes inside the lower part of the gill cover, behind the lower jaw  Fish Anatomy 
Breast Ventral surface of body between the gill opening and pectoral or pelvic fins  Fish Anatomy 
Bristle Stiff projection  Description 
Canine teeth Slender conical, often enlarged and elongated teeth  Fish Anatomy 
Carapace Shell or exoskeleton encasing the body Often used for crustacean Fish Anatomy 
Carnivorous Feeding on animals; flesh eating  Biology 
Cartilage A gristle-like material that is more flexible than bone, but serving a similar structural purpose  Fish Anatomy 
Caruncle A fleshy outgrowth  Fish Anatomy 
Casting The act of throwing bait or lure over the water,using a fishing rod  Fishing 
Catadromous Living mostly in fresh water and migrating to the sea to spawn  Biology 
Caudal Pertaining to the tail  Fish Anatomy 
Caudal fin Tail fin  Fish Anatomy 
Caudal keel A lateral ridge found just forward of the tail fin on the caudal peduncle of some fast-swimming fish  Fish Anatomy 
Caudal peduncle The base of the tail between the end of anal fin and the base of caudal fin; caudal wrist  Fish Anatomy 
Caudal wrist The base of the tail between the end of anal fin and the base of caudal fin; caudal peduncle  Fish Anatomy 
Cephalopods Member of the molluscan class Cephalopoda characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles converge at the head Typically octopuses and squids Biology 
Cheek Side of head below and slightly behind the eye  Fish Anatomy 
Cirri Plural of cirrus  Fish Anatomy 
Cirrus A small, fleshy protuberance, often subdivided into branches  Fish Anatomy 
Claspers External reproductive organs of male sharks, rays and chimaeras  Fish Anatomy 
Compressed body Body flattened laterally  Description 
Continental rise The gentle slope at the base of the continental slope  Habitat 
Continental shelf The flattened edge of the continental land mass between the coast and the continental slope Generally from the subtidal zone to about 200 meters depth Habitat 
Continental slope The sloping edge of the continental land mass Generally beginning from about 200 meters to 4000 meters depth Habitat 
Corselet A scaly covering forms behind the head and continues along the lateral line of some fishes Present on some scombrids Fish Anatomy 
Cranial Pertaining to the skull  Fish Anatomy 
Cranium Skull  Fish Anatomy 
Crenulate Scalloped or wavy edge  Description 
Crustacean Member of the subphylum Crustacea which include crabs, lobsters, crayfish, shrimp, krill and barnacles  Biology 
Ctenoid scale Scale with a spiny or toothed posterior margin  Description 
Cutaneous Pertaining to the skin  Fish Anatomy 
Cycloid scale Scale with smooth posterior margin  Description 
Deciduous scales Easily shed or rubbed off scales  Description 
Deep ocean current Current driven by density and temperature gradients Type of current Habitat 
Demersal Living on or near the sea bottom  Habitat 
Dendritic Resembling a tree or shrub  Description 
Denticle Small tooth-like structures  Fish Anatomy 
Depressed body Body flattened from top to bottom  Description 
Dermal Pertaining to the skin  Fish Anatomy 
Dimorphic Body shape and colour varies between the sexes  Biology 
Disc The flattened head and body of batoid fishes  Fish Anatomy 
Distal Near outer edge; far end from point of attachment  Description 
Diurnal Active during daylight  Biology 
Diurnal Active during daylight  Biology 
Dorsal Pertaining to the back  Fish Anatomy 
Dorsal fin Upper body fin Sometimes consist of 2 or more separated fins Fish Anatomy 
Dorsum The upper surface of the head or body  Fish Anatomy 
Drift fishing Fishing while the boat drifts with the current  Fishing 
Ebb tide A falling tide, the phase of the tide between high water and the succeeding low water  Habitat 
Ecosystem A community of organisms interacting with one another and the physical environment  Habitat 
Edentulous Without teeth  Description 
Elasmobranchs Cartilaginous fishes  Biology 
Electrocyte Cell that generates electricity  Fish Anatomy 
Elongate Extended in length  Description 
Emarginate caudal fin Caudal fin shape with margin slightly concave  Description 
Endangered species A population of an organism which is at risk of becoming extinct  Other 
Endemic Restricted to a particular region or place  Habitat 
Epibenthic Living on the bottom surface  Habitat 
Epipelagic Pelagic zone from the surface to the depths of 200 meters Also photic zone, euphotic zone, sunlit zone or sunlight zone Habitat 
Esca The lure on the end of the illicium of some fishes  Fish Anatomy 
Estuary The tidal reaches of rivers; partly enclosed body of mixed sea water and fresh water  Habitat 
Euryhaline Organisms that are able to adapt to a wide range of salinities  Habitat 
Eyed Side The side of a flatfish that has both eyes  Fish Anatomy 
Falcate shape of sickle or scythe  Description 
Falciform Curve like a sickle  Description 
Farmed fish Fish farmed using aquaculture techniques Can be contrasted with wild fish Other 
Filiform Threadlike  Description 
Fimbriate Fringed at the margin  Description 
Fin insertion The anterior or posterior point of attachment of a fin to the body  Fish Anatomy 
Finlets Series of small fins arranged along the back and belly usually close to the caudal fin  Fish Anatomy 
Fish finder Electronic sonar device which indicates the presence of fish  Fishing 
Flexion The action of bending or the condition of being bent  Description 
Fluviatile Living in river  Habitat 
Fly fishing A fishing technique using artificial fly or lure  Fishing 
Forked caudal fin Caudal fin shape with distinct upper and lower lobes and the posterior margin of each lobe relatively straight or gently curved   Description 
Fork length (FL) The length of a fish as measured from the tip of the snout to the center of the fork in the caudal fin Measurement for fishes with forked tails and which it is difficult to tell where the vertebral column ends Fish Anatomy 
Frontal ridge A ridge running along the top of the head along the midline  Fish Anatomy 
Furcate Forked  Description 
Fusiform body Body shape that is cylindrical and tapering at both ends  Description 
Game fish Fish caught for sport  Fishing 
Gasbladder A gas-filled sac lying under the backbone in the abdominal cavity, used in buoyancy Also referred to as airbladder or swimbladder  Fish Anatomy 
Gastropods Member of the molluscan class Gastropoda consisting of snails and slugs  Biology 
Gill Organ for exchange of dissolved gasses between water and the blood stream  Fish Anatomy 
Gill arches The bony arches to which the gills are attached  Fish Anatomy 
Gill cover The plate at the posterior end of the head that covers the gills; also called operculum   Fish Anatomy 
Gill filaments Principal site of gas exchange in the gill  Fish Anatomy 
Gill membrane membranes along the posterior and ventral margin of the gill cover  Fish Anatomy 
Gill opening Opening behind the operculum  Fish Anatomy 
Gill rakers A series of bony projections along the anterior edges of the gill arches Help prevent food from escaping through the gill opening Fish Anatomy 
Gill slits Slit-like gills openings in fishes such as sharks, rays, and skates  Fish Anatomy 
Gizzard An organ for grinding food; also called ventriculus  Fish Anatomy 
Glossohyal Tongue bone  Fish Anatomy 
Gonad An organ that produces gametes; a testis or ovary Sexual organ Fish Anatomy 
Gonopodium A modification of the anal fin of some male fish species to serve as a copulatory organ Sexual organ Fish Anatomy 
Gular plate Bony plate covering the underside of the head, behind the chin and between the sides of the lower jaw Clearly visible in Tenpounders family Fish Anatomy 
Gulf A large area of water bordered by land on three sides  Habitat 
Hadalpelagic  Pelagic zone between the depths of 6000 and 10300 meters  Habitat 
Hadal Zone Region of the ocean floor between the depths of 6000 and 10300 meters  Habitat 
Halocline A zone in which salinity changes rapidly  Habitat 
Handline Fishing line used without a rod or reel  Fishing 
Haremic A mating system where a group of female animals share a single mate  Biology 
Herbivorous Feeding on plant  Biology 
Heterocercal caudal fin The shape of a tail fin with a long upper lobe and a shorter lower lobe  Description 
Hyaline Translucent or transparent  Description 
Hypoxia Depletion of dissolved oxygen to a level which is harmful to aquatic organisms  Habitat 
Hypural The spines or bones of the last few vertebrae that supports the caudal fin rays  Fish Anatomy 
Ichthyologist Scientist who studies fish  Other 
Ichthyoplankton Fish eggs and larvae  Biology 
Illicium The modified isolated first ray of the dorsal fin that forms the “fishing rod" in anglerfishes  Fish Anatomy 
Imbricate Overlapping arrangement as in roof tiles and fish scales  Description 
Incised fin Fin membranes with a notched margin  Description 
Incisor The front and flattened chisel-shaped tooth   Fish Anatomy 
Inferior mouth Mouth position on underside of head with snout projecting in front of mouth  Description 
Interbreed Hybrid offspring produced by two different species  Biology 
Interdorsal The space on the back between the bases of the first and second dorsal fins  Fish Anatomy 
Interopercle The lower anterior bone of the gill cover  Fish Anatomy 
Interorbital The space on top of the head between the eyes  Fish Anatomy 
Intertidal The area of the shore covered at high tide and exposed at low tide  Habitat 
Intromittent organ A male copulatory organ in some internally fertilizating species  Fish Anatomy 
Isthmus The fleshy projection part of the underside of the head separating the gill openings  Fish Anatomy 
Jigging A technique of fishing using jigs or lures on a vertical line that moved up and down  Fishing 
Jugular Pertaining to the throat region  Fish Anatomy 
Juvenile Young; immature life stage  Description 
Juxtaposed Placed close together  Description 
Labial Pertaining to the lips  Fish Anatomy 
Labial furrows Shallow grooves around the lips of many cartilaginous fish  Fish Anatomy 
Labial papillae Fleshy projections around the lips  Fish Anatomy 
Lagoon A body of shallow water separated from the deeper sea by a shallow or exposed sandbank, coral reef, or similar feature  Habitat 
Lanceolate Spear-shaped or lance-shaped  Description 
Larva Early life stage of some animals which often looks very different than the adult  Biology 
Lateral The side or toward the side  Description 
Lateral line Series of sensory pores opening to the exterior located along the side of fish  Fish Anatomy 
Leader A wire or real strong fishing line that attaches to the end of the main line  Fishing 
Littoral The intertidal area of the shore  Habitat 
Lunate caudal fin Caudal fin shaped like a crescent moon; caudal-fin shape that is deeply emarginate with long and narrow lobes  Description 
Mandible Lower jaw  Fish Anatomy 
Maxilla The bone in the upper jaw behind the premaxilla  Fish Anatomy 
Median The middle or toward the midline  Description 
Median fins Fins that lie on the midline which include the dorsal, anal, and caudal fins  Fish Anatomy 
Melanophore Melanin bearing cell carrying black or greyish pigments  Fish Anatomy 
Mesopelagic Pelagic zone between the depths of 200 and 1000 meters  Habitat 
Midwater The middle stratum of water, well below the surface and well above the seabed  Habitat 
Molar Low,blunt,rounded tooth for crushing and grinding  Fish Anatomy 
Mollusk Member of Phylum Mollusca having a soft body and usually a shell  Biology 
Mud flat Coastal wetlands that form when mud is deposited by the tides or rivers, sea and oceans  Habitat 
Mud flat Coastal wetlands form by mud deposit  Habitat 
Nape The dorsal part of the body just behind the hard dorsal region of the skull and before the dorsal fin  Fish Anatomy 
Nasoral Region between the nostrils and mouth  Fish Anatomy 
Neap tide The tide with the least difference between the high and low level water During first quarter and last quarter moon Habitat 
Neritic Nearshore; the zone of water above the continental shelves  Habitat 
Nictitating membrane Inner eyelid  Fish Anatomy 
Nocturnal Active during nighttime  Biology 
Nuchal Pertaining to the nape  Fish Anatomy 
Oblique Slanting or sloping  Description 
Obtuse Blunt  Description 
Occipital Pertaining to the upper back part of the head or skull  Fish Anatomy 
Occiput Upper back part of the head or skull  Fish Anatomy 
Oceanodromous Fish that migrate only within marine waters  Biology 
Ocellus A round eye-like spot or marking with a marginal ring  Description 
Ocular Pertaining to the eye  Fish Anatomy 
Olfactory Pertaining to the sense of smell  Fish Anatomy 
Omnivorous Feeding on both animals and plants  Biology 
Opercle The large posterior upper bone of the gill cover  Fish Anatomy 
Opercular Pertaining to the operculum  Fish Anatomy 
Opercular spine Spine projecting from the gill gover  Fish Anatomy 
Operculum Gill cover; the plate at the posterior end of the head that covers the gills  Fish Anatomy 
Orbital bones The bones surrounding the eye  Fish Anatomy 
Origin of fin The anterior point of attachment of the fin to the body  Fish Anatomy 
Osseus Bone  Fish Anatomy 
Otolith A small bone or earstone in the inner ear of fishes  Fish Anatomy 
Ovate Egg-shaped  Description 
Ovigerous Carrying or bearing eggs  Biology 
Oviparous Producing eggs that hatch outside the body of the mother  Biology 
Oxbow A U-shaped bend in a river or stream  Habitat 
Paired fins Fins found on both sides of the body which include the pectoral and pelvic fins  Fish Anatomy 
Palate The roof of the mouth  Fish Anatomy 
Palatine The paired bones on each side of the palate  Fish Anatomy 
Papilla A small fleshy projection  Fish Anatomy 
Papillae Plural of Papilla  Fish Anatomy 
Papillose Covered with papillae  Fish Anatomy 
Pectoral fins Paired fins on the sides behind the gill cover  Fish Anatomy 
Pelagic Living on or in the open seas or oceans  Fish Anatomy 
Pelvic fins  Paired fins behind or below the pectoral fins, and in front of the anal fin Also called ventral fins Fish Anatomy 
Pharyngeal Pertaining to the back part of the throat, into which the gill slits open  Fish Anatomy 
Piscivorous Feeding on fishes  Biology 
Planktivorous Feeding on plankton  Biology 
Posterior Pertaining to the rear portion  Description 
Postorbital Region behind the eye  Fish Anatomy 
Predator Animal that captures its prey live  Biology 
Premaxilla Anterior bone in the upper jaw  Fish Anatomy 
Preopercle The upper anterior bone of the gill cover   Fish Anatomy 
Preorbital Region under and in front of the eye  Fish Anatomy 
Protractile Capable of being thrust out Often refers to the fish jaw Description 
Protrusible Capable of being thrust out  Description 
Proximal Nearest  Description 
Pseudobranchium A small patch of gill-like filaments on the upper inner surface of the gill cover  Fish Anatomy 
Ray Supporting element of fins  Fish Anatomy 
Recruitment Entry of individuals into a particular category  Habitat 
Red tide Discolouration of surface waters, caused by large concentrations of micro-organisms Most frequently happens in coastal zones Habitat 
Red tide Proliferation of marine plankton that is toxic and often fatal to fish This natural phenomenon is stimulated by phosphorus and other nutrients that are discharged into waterways by human beings Habitat 
Retrose Turned backward  Description 
Rhomboidal caudal fin Caudal fin having top and bottom unequal length/shape  Description 
Roe Eggs of fishes  Biology 
Rostrum Projecting snout or beak of the carapace of a crustacean  Other 
Rounded caudal fin Caudal fin shape with the terminal border smoothly convex  Description 
Rudiment A poorly developed structure  Description 
Salinity Saltiness of the water  Habitat 
Scale A small, flattened, rigid, and circumscribed plate on the external body  Fish Anatomy 
Scavenger Animal that feeds on dead organisms or organic matter  Biology 
Scute A modified scale Can be enlarged, horny, hardened, ridged, keeled, or spiny Fish Anatomy 
Serrate Saw-like notches along a margin  Description 
Setae Bristles or hardened hair-like projections  Description 
Sexual dimorphism Differences in physical appearance between the sexes  Biology 
Sinker A weight used to sink the bait or lure  Fishing 
Snout Front part of a fish that includes the mouth  Fish Anatomy 
Soft dorsal The posterior portion of the dorsal fin which is composed of jointed rays  Fish Anatomy 
Soft ray Laterally paired, segmented, and usually flexible and branched fin support element See spine Fish Anatomy 
Spatial Pertaining to distribution, distance, direction, areas and other aspects of space  Habitat 
Spatulate Spatula-like or shovel-like  Description 
Spawn To lay eggs; to produce offspring in large numbers  Biology 
Spine Unpaired laterally, unsegmented, unbranched and usually stiff and pointed fin support element See soft ray Fish Anatomy 
Spinous dorsal The anterior portion of the dorsal fin that is supported by spines  Fish Anatomy 
Spiracles Respiratory openings behind the eyes in sharks and rays  Fish Anatomy 
Spring tide The tide with the largest difference between the high and low level water During new and full moon Habitat 
Standard length (SL) The distance from the anterior most point on the fish to the posterior extremity of the hypural plate, the expanded bones at the end of the backbone that support the caudal fin  Fish Anatomy 
Stripe An elongated nearly straight horizontal marking Marking Description 
Submarginal Adjacent to the margin  Description 
Subopercle The lower rear bone in the gill cover  Fish Anatomy 
Suborbital Region below the eye  Fish Anatomy 
Subterminal mouth Mouth position that is oriented behind the snout and faces downward  Description 
Subtidal The ocean floor below the low tide mark  Habitat 
Superior Above or on the upper surface  Habitat 
Superior mouth Mouth position with the snout behind the anterior opening of the mouth  Description 
Supraorbital Region above the eye  Fish Anatomy 
Surface ocean current Wind driven current Type of current Habitat 
Surfcasting Fishing from a shoreline using a rod to cast into the surf  Fishing 
Swimbladder A gas-filled sac lying under the backbone in the abdominal cavity, used in buoyancy Also referred to as airbladder or gasbladder Fish Anatomy 
Tackle Fishing equipment  Fishing 
Taxonomy The science of classifying organisms  Biology 
Terminal Pertaining to at the end, or situated at the end  Description 
Terminal mouth Mouth position with the opening of the mouth even with the tip of the snout   Description 
Terminal tackle The gear attached to the end of the fishing line  Fishing 
Thoracic Pertaining to the chest  Fish Anatomy 
Tidal current Alternating horizontal movement of water associated with the rise and fall of the tide as the earth rotates Type of current Habitat 
Tide The rise and falling of seas, oceans and rivers caused by the gravitational pull of the moon and sun  Habitat 
Total length (TL) The distance from the anterior most point on the fish to the posterior edge of the caudal finfold  Fish Anatomy 
Toxin Poisonous substance produced by a living organism  Biology 
Trawling Fishing technique with the boat moving and the fishing net trailing behind  Fishing 
Treble hook A hook with three sharp points  Fishing 
Trolling Fishing technique with the boat moving and the fishing line trailing behind  Fishing 
Truncate caudal fin Caudal fin terminating abruptly in a square end  Description 
Tubercle A small lump or excrescence  Description 
Turbidity current current of rapidly moving, sediment-laden water that is heavier than clear water and therefore flows downslope along the bottom of the sea or a lake Type of current Habitat 
Undulated Having a wavy surface, edge, or markings  Description 
Vent Anus; opening of the intestine through which wastes are excreted  Fish Anatomy 
Ventral Pertaining to the abdominal or lower surface of the body  Fish Anatomy 
Ventral fins Paired fins behind or below the pectoral fins, and in front of the anal fin Also called pelvic fins Fish Anatomy 
Ventriculus Gizzard; an organ for grinding food  Fish Anatomy 
Vertebrae The bones of the spinal column  Fish Anatomy 
Vertical fins The median fins which include the dorsal, anal, and caudal fins  Fish Anatomy 
Vestige Small or underdeveloped structure  Description 
Villiform teeth Slender teeth forming velvety bands   Description 
Viviparous Giving birth to living offspring that develop within the body of the mother  Biology 
Vomer An unpaired median bone on the roof of the mouth  Fish Anatomy 
Wetlands Areas of land where the soil is saturated with moisture, such as swamps and mangrove forests  Habitat 
Yolk Sac A bag-like ventral extension of the gut containing nutrive materials  Fish Anatomy 
Zooplankton Small aquatic animals that are suspended or swimming in water  Biology 
Showing 322 items