
1) Fish 2) Plectognath 3) Plectognath fish 
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1) Leatherfish 2) Leatherjacket 
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 Filefish (also known as foolfish, leatherjackets or shingles) are tropical to subtropical tetraodontiform marine fish of the diverse family Monacanthidae. Found in the Atlantic, Pacific and Indian Oceans, the filefish family contains approximately 107 species in 26 genera. Filefish are closely related to the triggerfish, pufferfish and trunkfish. ...
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• (n.) Any plectognath fish of the genera Monacanthus, Alutera, balistes, and allied genera; -- so called on account of the roughly granulated skin, which is sometimes used in place of sandpaper.
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any of the shore-frequenting marine fishes of the family Monacanthidae, found in warm seas around the world. Close relatives of the triggerfishes, ... [1 related articles]
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http://www.britannica.com/eb/a-z/f/24
 File'fish`  noun  (Zoology)
File'fish`  noun  (Zoology) Any plectognath fish of the genera 
 Monacanthus , 
 Alutera , 
 balistes , and allied genera; -- so called on account of the roughly granulated skin, which is sometimes used in place of sandpaper. 
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http://www.encyclo.co.uk/webster/F/28

[
n] - narrow flattened warm-water fishes with leathery skin and a long file-like dorsal spine
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 noun
 noun narrow flattened warm-water fishes with leathery skin and a long file-like dorsal spine
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https://www.encyclo.co.uk/local/20974

any of several flattened marine fishes of the family Monacanthidae, having an elongated head with a small mouth and small, spiny scales. · a triggerfish.
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https://www.infoplease.com/dictionary/filefish
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