Minnow is a general term used to refer to small freshwater and saltwater fish, especially those used as bait fish or for fishing bait. More specifically, it refers to small freshwater fish of the carp family. They are also known in Ireland as pinkeens.
Smaller fish in the subfamily Leuciscinae are considered to be "true" minnows:
Bluntnose Minnow (Pimephales notatus): The Bluntnose minnow is a primary bait fish for Northern America (more specifically Ohio) and has a very high tolerance for variable water qualities, which helps its distribution throughout many regions. The snout of the Bluntnose minnow overhangs the mouth, giving it the bluntnose. There is a dark lateral line which stretches from the opercle to the base of the tail, where a large black spot is located. The average size of the adult is approximately 5 cm (2 in). 'Pimephales
Common Shiner (Notropis cornutus): These fish are one of the most common type of bait fish and are almost exclusively stream dwellers. The Common Shiner can be identified by the nine rays on its anal fin and terminal mouth. This minnow is typically bluish silver on the sides and greenish blue on the back., save for breeding season in which case the male gains a rose colored tail and anal fin. The Shiner grows about 5–10 cm (2–4 in) within one year and reach a size of 13 cm (5 in) at adulthood. Another common "shiner" bait fish is the young version of the European chub (Leuciscus cephalus or Squalius cephaloides) which is quite easy to catch. Notropis potteri is known as the Chub Shiner.
Common Emerald Shiner (Notropis alterinoides alterinoides): Common Shiners are most abundant in the Great Lakes of North America, primarily Lake Erie. The name of the Emerald Shiner comes from the greenish emerald band that expands from the back of the gill cover to the tail. This type of minnow has a short, rounded snout, the only difference between the Common Emerald Shiner and the Silver Shiner is that the Silver Shiner has a longer snout and a larger eye. These fish grow to an average length of about 6 cm. This is one of the most common bait fish used in the Lake Erie region of Ohio and many fisherman hold it over all other bait.
- Cheat minnow, a species in the genus Pararhinichthys
- Cutlips minnow, a species in the genus Exoglossum
- Desert minnows, fishes in the genus Dionda
- Eurasian minnows, fishes in the genus Phoxinus
- Fathead minnow (rosy-red minnow), a species in the genus Pimephales
- Loach minnow, a species of the genus Rhinichthys
- Short levered minnow, a species of the genus Minnellinus
- Pikeminnows, fishes in the genus Ptychocheilus
- Pugnose minnows, fishes in the genus Opsopoeodus
- Silverjaw Minnow, a species in the genus Notropis
- Longjaw Minnow, a species in the genus Ericymba
- Silvery minnows, fishes in the genus Hybognathus
- Suckermouth minnows, fishes in the genus Phenacobius
- Vietnamese Cardinal minnow, a species in the genus Tanichthys
- White Cloud Mountain minnow, a species in the genus Tanichthys
Top Minnow (Poeciliopsis occidentalis occidentalis): An endangered minnow species which are found primarily in southern New Mexico and Arizona. The drop in the Top Minnow population can be linked to the introduction of the Common Mosquitofish. This type of minnow grows to a length of 6 cm (2 1⁄2 in) with the females growing to be larger than the males. During times of breeding males turn black while females and non-breeding males are tan or olive-green. The diet of the Top Minnow consists of bottom debris, vegetation, and small crustaceans.
Common Mosquitofish (Gambusia affinis): The Mosquitofish is a very small minnow which has received its name for its fondness to mosquito larvae. The mosquitofish usually reaches a length of only 2.5–5 cm (1–2 in) long. This is a peculiar fish because the male has a "modified" anal fin and female gives birth to live young. much like their related cousins the Guppy.
Other fish specifically called minnows include
- in the Southern Hemisphere, some fish in the family Galaxiidae, in particular those of genus Galaxias
- in Southeast Asia, the danionins
- the Drakensberg Minnow (Barbus aspius) from South Africa
- the Maluti Minnow (Pseudobarbus quathlambae) from Lesotho
- the Falklands minnow from the Falkland Islands
- the Piketop minnow (Belonesox belizanus) are confused for the northern pike, (Esox lucius), also called "Minnow" for the little size.
- the Minnows of The Deep (Cyclothone sp.), small bioluminescent bristlemouth fish approximately 3" long 
Catching minnows for bait
Using minnows as baits can be seen by many fishermen as one of the most effective methods for fishing. Bait minnows can usually be found in any bait shop, especially ones near a body of water, but many anglers prefer to capture their own.
A method in which a fisherman finds a school of minnows and using a fine meshnet scoops through the school, bringing the net back out of the water in one motion. This method is primarily used on the shore near the bank of a stream or a shallow area of a lake or pond.
A seine is a large net, sometimes being 40 ft (12.192m), which has small weights attched to the bottom. These small weights help to keep the net vertical in the water while two people hold either end of the net and drag it through a spot where minnows are suspected to be. This method is good for catching a variety of bait fish and is one of the oldest methods for catching fish.
A wire trap is made of two half-cylinders with concave cones which end in small openings at either end. These two halves are connected together after some sort of bait to entice the minnows has been placed inside. The wire trap is connected to a length of line which is fastened to something on the bank or a float. Minnows are attracted inside the trap by the bait, swimming into the small opening at either end, after they have found their way in it is very difficult for them to escape. This technique is one that requires more time, but less attention.
- cf. pinkeen and pink, Oxford English Dictionary, Second Edition.Pinkeen Merriam-Webster Dictionary. Retrieved: 2011-12-11.
- Trautman, Milton B. (6 July 1993). "Bluntnose Minnows in Ohio". Department of Natural Resouces Ohio Division of Wildlife Document. 189 (R778).
- Trautman, Milton B. (30 June 1993). "Common Shiner in Ohio". Department of Natural Resources, Ohio Division of Wildlife Document. 189 (R778).
- Trautman, Milton B. (30 June 1993). "Common Emerald Shiner in Ohio". Department of Natural Resources, Ohio Division of Wildlife Document. 189 (R778).
- Topminnow Map. 2 June 1983.
- Trautman, Milton B. (6 July 1993). "Mosquitofish in Ohio". Department of Natural Resources, Ohio Division of Wildlife Document. 193 (R778).
- Proujan. C., (1979), SECRETS OF THE SEA, 2ND ED.,London: Reader's Digest Association Limited. Pg.60
- TubeDude. "Minnows" (PDF). "TubeDude". Retrieved 3 April 2012.
- The dictionary definition of minnow at Wiktionary